I have the copperhead and the G5, both mice are very good.
Plus points for the copperhead, more buttons, it glows ooooh!!!. Its not a right handed mouse. It will work for right and left handers. On the fly sensitivity change.
Negatives, its too light, but you can buy a weight pack. Its small shape is unforgiving on large hands. Whatever buttons you have by your little finger are impossible to reach.
The G5 however I much prefer.
Plus points on the fly sensitivity. Weight pack to change to your preference. More comfortable on the hand than the copperhead. The left right wheel switch is nice and can be bound to be useful in games.
Negatives, only one thumb button, I also have a MX1000 that is phenomenal on the amount of buttons. If your left handed its not for you.
The new iteration of the G5 has more buttons. Out of the copperhead and G5 I definately prefer the G5 but its a matter of taste. I do like the heavier weight I can put in the G5.