Everything is detailed, but not crazy detailed. That's the thing with Bachmann, most of the sets are good and everything works, but you're not going to lose yourself in the details. I think with a little weathering the locomotive and tender will look much more "real", along with the rolling stock.
I think a lot of the issues people experience are from poor setup and tracking issues. If the front axle is not on the track (which is hard to tell as it's mostly hidden), it will derail a lot. If the rear isn't on the track (again, hard to see), it will derail. If the tender isn't on the track, it will derail. There's a lot of alignment needed to get the locomotive on the track and running right, but once that's done it runs great.
Overall it's a solid set, and for the price you can't really beat it.