I’m sitting in front of a Retina 5k iMac right now typing this to you. (It was supposed to arrive on Friday but came a few days early.)
It’s the most gorgeous desktop display I’ve ever seen, breathtaking at first and then like all great work becomes invisible and you forget that there was ever a time when displays weren’t this beautiful. (Until you look at some lesser monitor again.)
I’ve been using 4k displays, the Sharp and the ASUS, with Mac Pros for a few months now, and to be honest they come close, but this takes the cake in every possible way, including the design and aesthetics of the computer/display itself which is laptop-thin at the edges. If you’ve been on the fence, and you’re okay with the tradeoffs an iMac has in general, get one. I can’t wait for them to do a 5k Thunderbolt display (but it sounds like it might be at least a year away).
P. S. If you’re looking for a gift for the iMac that has everything, consider a slipper to keep its feet warm.