Upload & Sell: Off
I love mine (2011 27" base configuration upgraded to 16GB of ram). The screen is beautiful, IMO. Glare can be an issue if you're using it in a room with windows to your side or behind you. Otherwise, it's a non-issue. I've calibrated mine with an i1 Display 2 coupled with ColorEyes software and my printing results are accurate (close enough for me).
It's hard to beat the value of an iMac (speed with a nice built in screen). However, I'm going to be selling my as soon as my new macbook pro arrives. I just need something that's more portable. But if I didn't... iMac is awesome.