BF3 Sensitivity Help?!

Hi!
So. im having a bit of an issue regarding sensitivity in BF3. It feels like no matter what sensitivity i use, Real Slow, slow, half n half, fast, Real fast, my hand cant get comfortable.
Ive tried various things, to no avail. Any suggestions regarding what i should do?

I use a Logitech M570 thumb trackball, btw.

Thanks!

[dflynn]

Hmm.. anyone else with a thumb tracker ball.. I can't see how that would be very comfortable

[dflynn]

I have my sensitivity set pretty low for ground and when I get into a vehicle I can adjust the sensitivity with a button to increase or decrease depending on what I am doing..

Yeah, I have the Logitech MX518 mouse, has sensitivity buttons on it. But why would you use a trackball for gaming?

I know Boo_yaa used to use it and he could never get it dialed in right to make it work for quick movements with-out over shooting it or he would be to slow to be effective.