How much is the g5 and what make is it?
I prefer a normal/low dpi mouse for playing FPS games such as BF2, there's nothing worse than having a too sensitive mouse when trying to aim accurately, i used to use a MX518 but ditched it for a Microsoft Intellimouse which is a five button wired optical mouse.
Logitech MX518 - best purchase I've made on a mouse. Works great in tandem with the Logitech G15 keyboard too....
http://www.logitech.com/index.cfm/products/details/GB/EN,CRID=2464,CONTENTID=10121
D.