Samsung are the best at the moment for picture quality and sharpness, i found the Samsung Bordeaux LE32R74BDX 32" monitor to be the best around at the moment for the bang per buck.
if you go into a re-tailer on the high street they will have their screens on display so you can compare, how i found out anyway, but when it comes to playing games i dont really think it matters what brand you buy as it doesnt really show up much of a difference.