Personally I really hate iMac as a product. All-in-one computer is the worst of both worlds. It has to be thin it's incapable to handle the heat of desktop chips and/or graphics so it must do with some laptop parts. But it's not really portable either since it has 24" display or more, and you have to plug it in all the time? I don't know why anyone would pick an iMac over a true desktop, or a laptop.
I've been burned buying an 27" iMac once for various problems it had, I'm glad that Apple decides to keep display and Mac separate despite some of its usual quirks (i.e you need a Mac to use the Studio Display to its fullest potential), but it's a nice change of direction.