I had a 20" Samsung monitor which was not only affordable but it was also extremely good looking and performed great. I'd always go for a 20" model because the 22" monitors on the market tend to have the same 1680x1050 resolution, meaning they're not as sharp or crisp to look at.
Try this one or this one.
You may want to check this out : http://discussions.apple.com/message.jspa?messageID=6189316
Of course it does not necessarily mean that you will have problems.
Do you have any other suggestions that you think would be better?