We are still very much in the infancy of home 3-D printing, similar to personal computers in the early 1980's. That being said, we are now past the "kit" stage and on to fully assembled and tested models.I have researched 3D printers since October 2012 and waited patiently for a fully assembled model that met certain requirements: Heated print bed, Self leveling, Metal print head, Metal frame, Good FREE Warranty of at least one year, Great Customer Service via phone and email, and American made quality, all for under $1,500. That is a lot to ask for and until the Lulzbot Mini shipped from Colorado in January of 2015, I couldn't find anything that matched my requirements. But I still waited to see what actual owners were saying. Then a few months ago, PC Magazine gave the Mini their first ever purchase recommendation for a 3-D Printer with a rave review. That, along with other reviews finally pushed me over the edge and I placed my order via Amazon.Now you may notice that I am giving the Mini 4 out of 5 stars as there is still room for improvement. The first Mini I ordered had a few problems that were not immediately apparent. It had a defective Y axis belt that quickly wore out in a few days. A call to the factory in Colorado was answered by a human who apologized stating that they had a bad batch of drive belts get through and he would send me out a free replacement. The printer was down for a week while I waited for the belt. Replacement was simple and I was up and printing again in no time. Then after a few more prints, filament became stuck in the hot end. By stuck, I don't mean jammed which can be a common problem with 3D printers, I mean stuck and stuck hard. I used every suggested strategy to clear it out but nothing worked. The PLA filament was melted/stuck above the heated tip (?) and nothing could free it! Very frustrating. Two problems right off and that was it for me. Perhaps I got a lemon. I returned it to Amazon and requested a replacement.My second Lulzbot Mini arrived only two days after the first was picked up as Amazon shipped it out to me immediately without waiting for the first one to be returned. Wow, class act Amazon! Great customer service!My new second Mini wasn't without a problem either but it was easily solved. The Z axis (up/down) is controlled by two independent motors but electrically controlled in unison. The problem was that they were out of alignment. On my first print, you could hear the left side strain under the pressure. Upon checking self leveling numbers of the four corners I discovered that the physical alignment was severely off and thus was putting a strain on the print head alignment shaft. A simply fix was to shut down the machine and align the vertical lead screw by hand turning it at the Z motor, then rechecking the alignment. Like I said, easy fix. All I could think of was that the assembly person who tested the printer before it left the factory couldn't hear the obvious straining of the left lead screw.I've been printing successfully ever since with a failure rate of only 5 to 7% which is extraordinary and usually my own fault due to incorrect settings! I keep a database on each print as to name, material, time printing, cost, etc. and of course, the quality of the final product and I must say that I am extremely impressed with this little workhorse. It is simply an amazing, high quality 3D printer and there is currently nothing better in this price range.THE GOOD: 1) Self Cleaning Print Head. 2) Self Leveling Print Bed (I believe this is the Most Important Feature as every 3-D printer should have this!). 3) Heated Print Bed that does NOT require any tape or hairspray or glue or anything else to get proper adherence of the part. It is a glass bed covered in a material called PEI which is amazing. When heated it gets sticky. When cooled it is slick and your part usually just pops off or needs just a little help to be removed. Outstanding material! 4) Hexagon Metal Print Head that can be heated up to 300 C (572 F) so you are not limited like others to one or two materials. You can print in several types of plastics including nylon as well as wood/PLA and metal/PLA mixed filament. There are many, many materials you can use and more are being added monthly. (Note: Flexible materials require a different print head which is now available from the manufacturer.) 5) Useful Tool Kit is Included. 6) One Year Warranty with a 30 Return Policy if you don't like the machine. Now I ask you, what other 3-D printer has such a great FREE Warranty and return policy? (But just to be safe, order yours like I did from Amazon as their return policy pays for shipping as the factory policy makes you pay for return shipping to them.) 7) Made in the USA with readily available parts.THE BAD: 1) Small Print Bed at 6 X 6 X 6.2 inches. I am finding however, that 85% of everything I want to print fits just fine. If something is larger, I can print it in two (or more) pieces and glue it together later (which I have done on a T-Rex spine and ribs). 2) Must be attached to a computer to operate. This is not a stand alone machine like many others. This is an inconvenience only, as I am not planning on moving the unit out of my office. Of course you can continue to use your computer while it prints, but be careful not to accidentally shut down the program or disconnect the cable (yes, I did just that... but only once!) as everything comes to a crashing halt and your print will be ruined. (Note: There is a non-factory option to add a wireless tablet to the Mini to free it from the computer connection. It runs about $300.00.) 3) Keeping little hands and faces out of the printer. The Mini has a metal perimeter cage without enclosures. The print head can heat to 572 degrees F (300 C) and thus is a serious burn hazard. Since it isn't enclosed, you may also find yourself constantly warning others of the potential hazard of burns and mangling of fingers if one isn't careful to respect its working borders. My spouse and friends have informed me that they get a strange hankering to touch the machine and/or the part being printed while it is working. This would be a problem if left unattended which I would highly recommend against for reasons including this, but also for others... things can and will go wrong and you will be better off if you can stop the machine quickly. (There is a fix: Currently there is a non-factory made Plexiglas enclosure for sale online for about $119.00). 4) Be prepared to put your life on hold and host guests and relatives who want to see/use your amazing 3-D printer. This machine makes kids out of adults as they watch in fascination as it works away on your print. It's amazing to watch people just stop and stare. I've already caught a friend with his face inside the machine watching closely the layers being extruded not realizing that any moment, he could have had his nose burned!All being said, this is (ALMOST) a Plug & Play 3-D Printer unlike any other currently on the market. It it truly a quality machine capable of printing in high resolution of between 50 and 500 microns though you will usually print in 140 to 250 microns. The print quality has topped anything I have come across in this price range and above to $3,000.00. I carry some parts I have made with me daily. Compared to what I have seen and examined from other available 3-D printers, the Lulzbot Mini has topped them all in quality, price, performance, and cost of ownership which includes material.In conclusion: You can purchase a less expensive 3-D printer but you will not be happy without a heated self-leveling bed. You can pay a few thousand dollars more but gain very little if anything. You will not find a better built, reliable, and cost effective U.S. made printer on the market today. That is saying a lot, but the Lulzbot Mini is a lot of printer for the money. In fact, I'm planning on buying a second one soon just to print flexible gaskets! It's that good!September 2016 UPDATE:It's been eleven+ months since my Mini purchase. I've printed around 400 different parts, toys and "things" since. Many my own design and others downloaded. Overall, I've had about a 5% failure rate usually due to a mistake in settings. However, sometimes I've found that downloaded files are corrupt in their design. It happens. But I am here to report on the condition of my Mini:My Mini is still going strong! The one visible wearing part seems to be the PEI surface on the heated print bed. Since most of my prints were printed in the middle, the PEI surface has become detached there, showing as a discoloration of the reddish surface. You can feel that it has lifted away from the glass bed there. This has created a minor problem as filament won't stick there properly. The easy fix is to adjust your part to print slightly away from the center. The PROPER fix is to order a replacement PEI sheet that runs only $25. It's on my list...The only other minor problem is that the left side Z axis rod/motor assemble has begun to "click" at each revolution. It doesn't affect printing but is annoyingly loud. I suspect this is just normal wear and tear but I'll need to address it soon.That being said, I have total confidence in my Mini and my purchase. I've compared it to other models available and it is still the best working, best value around for a 3D printer. It's simply a reliable workhorse!The Mini is so good that the manufacturer decided to upgrade their larger TAZ 5 to a TAZ 6 that incorporates the Mini's self cleaning and self leveling features! Had the new TAZ 6 been available when I purchased my Mini, I would have purchase it for it larger print bed and available dual print heads!In conclusion, "Am I happy with my Mini purchase?" YES, EXTREMELY SO! But if you can afford the extra $$$, BUY THE NEW TAZ 6! Both machines are EXCELLENT but the TAZ 6 is (almost) twice the size (and twice the price)! Either way, you really can't go wrong!! :)2017 UPDATE:Just a quick update: I decided to have the factory look over the Mini as the "clicking" sound needed to be addressed. They fixed that and also found a bad Y switch and related short in the wiring. I did have to pay for the shipping to the factory which ran about $50 but the Mini was still under warranty and thus the repairs were free. Great customer service and I had the Mini back in about a week. Note: Keep the original box and shipping materials as a replacement box will cost you an additional $50 and is required for shipment.My Mini is working away now reliable as always surpassing the 600th item. Truly a Workhorse! :)