MX 518 is a LASER mouse, but uses Laser Engine 1 technology with 1600 dpi, whereas G5 has LASER Engine 2 tech with 2000dpi.
Its better to stretch 1k more to get the G5 itself. Its got lot more features,perfomance and comfort.
G5's feet are best and it has weight adjustment and its software support is superb[ but only work well in Xp, nut even in 2000].
Im currently using the iball one and its really gud for the price. Good controll of the crosshair and comfortable on hands too.Go for it if u are low on budget.
well most gamers have there own views, some of the best professional gamers are still on 400 dpi optical mouses( the intelli series from microsoft being an example), while some are on 2000 dpi monsters.
if you take my opinion then mx518 + a good cloth pad is unbeatable.
Even if its called an 'optical mouse', it uses laser engine 1 technology from logitech. So technically speaking its a laser mouse. Also the mouse seems to be very large, so some may not find it very comfortable. But due to the desing of G5, even people with smaller palms too can use it comfortably.
And u mentioned bout problems in Razer mice, but there are more s/w problems than for logitech than of razer.
Ive used MX 518, G5, MS laser 6000 etc and also had chance to use some best mousepads like razer mantis[on a friend's place: a distant friend so cudn't ask him to get one].
I personally liked the G5 one. As for me, i dun like to spend 3.5k for a mouse[even if its worth it], so went for iball for 750 bucks.
MX518/DeathAdder/DiamondBack are all optical. Copperhead/G5/Habu/MS Laser are laser mice. Its pretty easy to see what sensor it is... just turn the mouse upside down . Also IMHO the Mantis is a POS. Laser performs well only on the right surface. On cheapo surfaces, it sucks.