If you're looking to do double / triple monitor gaming, with the ATi card, you're going to have to buy an Active Display Port adapter (as far as I'm aware.. I think you can use a passive for anything under 1680x1050) which are $100 each. And if you really do want to do double / triple monitor gaming.. definitely buy the third monitor. The bezel right in the middle of the action would kill me
I have two Acer 1080p 21.5" monitors purchased about two years ago. Amazing quality and I got 'em for ~$140 each.
Also, just if you didn't know, the monitors all have to be the same size and refresh rate to work with EyeFinity.