my teammate who is sniper uses 800x600, also some pros like aslak uses 800x600, better resolution for awps, i don't know why, but they prefer to use 8x6
i usually play awp on 800x600. when i changed the resolution to 640x480 i didn't hit anything with awp, i don't know why...the feeling is better with 800x600
I play on 1280x720 becouse i'am in notebook xD
But I advise you to play in AWP at 1280x720 & 800x600 if you want a goo graphics in cs only. Sorry for my English) i'am Ukrainian xD