I have a G9 and love it. It's a bit on the expensive side though. Out of that list, I'd get the G5 - I personally don't like the feel of the sidewinder that much. Some people may disagree though - different people like the feel of different mice.
------------------------------Asus P6T deluxe
i7 965 @ 4.2GHz (200*21), 1.384V
12GB Corsair Dominator DDR3-1600 CAS 7
Reply to cjl
Vice versa. If I remember right, the only real difference between the two is that the MX518 uses an LED optical sensor, and the G5 uses a laser sensor.
------------------------------Asus P6T deluxe
i7 965 @ 4.2GHz (200*21), 1.384V
12GB Corsair Dominator DDR3-1600 CAS 7
Reply to cjl