If you can afford it your gaming experience will be greatly enhanced by going with a 1080p monitor.
Can you please tell us what other hardware will be in this in the PC.
With your 1600 x 900 monitor you will end up using more post processing such as AA etc if you want to make things look the best you can.
When I updated my Monitor to 1080p I wished I had done it earlier.
I have a BenQ monitor 22" and 1080p as it fits on my bench. I have no complaints about it and you don't need to but an expensive one either.