I can understand your situation. I really liked, and mean really liked the old Apple displays. But the new ones… oh my god. They're actually stunning in person, it's difficult to explain just how good they look.
One thing worth asking though before getting more advice is this: what display do you have at the moment, and what aspects of your current display do you like/dislike most? Weigh them up, then decide.
FWIW, my maxim when making such decisions is either 'buy the cheapest' or 'buy the best'. The former you can sell on and replace whenever you want, the latter will last several years.
If it's any use, I've only seen one other flat panel display that even compares to the new Apple line in terms of aesthetics (but not necessarily picture quality) and that would be this
LG display which was my dream display until the new Apple displays came out.