Before providing my opinion on this Samyang Lens, I would like to describe myself as a middle aged advanced amateur photographer. I am not a pro but photography has been a hobby of mine for 20 years and in the last 10 years, I have been lucky to be able to purchase some professional L lenses and primes. Therefore, I feel I have some experience that I can draw upon to compare this ultra wide angle Samyang with other lenses in my camera bag.First off, I want to mention at the time I am writing this review (10/12/2013), the product photographs in the Amazon listing is incorrect. They have a 35mm focal length Samyang sitting in as the Canon version of the 14mm lens. I took a chance with Amazon and the lens that arrived at my door is the correct 14mm lens. Therefore, no worries you will get the right lens sent to you. Second, and unfortunately for me but perhaps fortunately for you ... The Samyang SY14M-C 14mm f/2.8 ED AS-IF UMC is optically identical to the Rokinon FE14M-C 14mm f/2.8. Unfortunate for me because the same lens branded with the Samyang name is or was at the time of my purchase about $60 more expensive. Had I known both lenses were identical, I would have gone for the Rokinon branded lens and saved some money. So if you could avoid the mistake I did, go for the Rokinon. Same manufacture, same factories, same workers make both lenses. But it's just not worth my time to send the Samyang back and get the Rokinon to get the extra $60 back. Perhaps the prices and photos will be corrected by the time you read this review.Now for the lens. This lens is incredibility sharp and I am quite impressed at how sharp it is on my Canon 5D Mark 3. The closest lens I have to compare it to is the newer Canon 24-70 f/2.8 L Mark 2 and the Canon 50mm f/1.4. This lens, in terms of sharpness really can hold its own along these other lenses. I bought the Samyang lens to get something wider than the 24-70 and I am very happy I did. The lens is sharp from edge to edge on the 5D Mark 3 full frame body. The focus ring turns very smooth with long travel to obtain precise focus. The aperture ring feels solid and has no lose play in it. When you set the aperture, it stays put with confidence. The mechanics of the entire lens really gives the impression of quality just as much as the more expensive L lenses but in a plastic body of course. But the plastic doesn't feel cheap.Lens distortion can be easily corrected in Light room and Photoshop by installing the appropriate lens profile for the Samyang. Download the "Adobe Lens Profile Downloader" from Adobe's website and then filter the profiles by your camera body (eg. Canon 5D Mark 2) and download the appropriate RAW profile. Google "Markus Keinath - Samyang 14 mm / 2.8 IF ED MC Aspherical" for detailed instructions. Even if your particular camera body isn't listed, if you know your camera body is a full frame, pick another full frame model, if your body is a crop sensor body, then pick another body with a APS sensor body and it should work just fine.My one gripe about the lens and it has more to do with me than the lens. If your eyesight is less than perfect, it is almost impossible to manually focus this lens looking through the viewfinder. Everything in the viewfinder seems like it is in sharp focus no matter how the lens is already focus. Using a magnified LiveView becomes essential in getting this lens in sharp focus. But you might also encounter additional problems both in bright sun and low lighting. Sometimes the bright Sun just washes out the LED on the back making the job of focusing the lens much more difficult. In low lighting condition, you will probably either have to temporary open up the aperture to let more light into the camera to be able to focus or decrease the shutter speed. Then remember to correct the exposure again before taking the picture, otherwise you will end up disappointed with over exposed photos. Because it is completely manual, you will not receive any focus confirmation beeps, chirps or indicators from the camera body or it's viewfinder as you would using a Canon AF lens in manual mode. Focusing with this lens is exactly like trying to focus it when the camera body is off; there is zero assistance to guide you to getting a sharp image. It will be 100% on you to get the lens as focus as necessary.The plus side of this, because the lack of AF will slow you down, it will force you to think about composition within the frame. I think that is a great thing. In addition, this is definitely not the right lens to shoot fast moving subjects unless you have plenty of light that you can choose a small aperture setting for a deeper DOF. This is a great lens if you have patience, but if you do not, it will aggravate you quickly.I also recommend checking out some of the other views here on Amazon listed under the Rokinon brand name. Moreover, visit some of the popular photography forums on the net including Dxomark review. Best of luck.===== UPDATE JULY 10, 2014 ======I came back to my review today to pass on some helpful information that I uncovered this summer using my lens. Bright sunny days will be a challenge when you try to focus this lens outdoors. The glare from the sun off the back LCD will frustrate almost anyone, myself included. I began to have some fun with a firmware hack called "MagicLantern" popular with videographers. Google it to find the website and see if your particular camera body is supported, not all Canon bodies are supported. MagicLantern gives Canon bodies extra features that are not normally available. Among the many features is "focus peaking", basically a tool to help you focus a lens manually. Sony Alpha shooters are already familiar with this feature but MagicLantern provide this cool feature to Canon users. A second feature in MagicLantern is "Trap Focus". When Trap Focus is enabled in the MagicLantern menu, you can have your camera body trigger the shutter button when an object/subject comes into focus. I enable Trap Focus with AF ON button on the back of my 5D Mark III to prevent premature firing of the shutter. It will only fire if I am holding the AF ON button on the back and the subject comes into focus.Something else you might want to consider buying is a rear LCD hood loupe. There are many available, some more expensive than others. I personally chose the hoodman hoodloupe, but do your own research to find out which one is best for you. A hoodloupe improves viewing the rear LCD by blocking out the sun. Combining MagicLantern Focus peaking, Trap Focus and a LCD hood loupe will significantly reduce frustration in focusing this lens and it works well for recording video as well. I hope this information proves helpful for your photography. Best of luck.