Tuck_n_Tay :
I had also looked at a Logitech g600, what would you think of that?
it's good mouse but it's designed for MMO Games ( WOW , LOL , Dota , ETC.... )
In my opinion it's not a good choice for FPS Games .
google this : " what is the best mouse for Counter strike ( FPS games ) " and check what they are saying .
must of them will say the G500 / MX518 ( it's kinda old ) / Logitech G5 / Steelseries Sensei .
Btw , i need to change my mouse too , i would go for the logitech G500 or G5 for logitech side
and the sensei for the steelseries side , i play CS:GO mostly so i think the G5 will be my choice .