Mouse thumb button

[Nanobot]

Have an old Dell branded Logitech wheelmouse which is getting flaky. Been looking around the forums and there's good talk of the MX518.
I've been looking at all different brands of mice with thumb buttons but here's the quandary - on the old Logitech wheelmouse I have, the thumb button is on the right side as with most mice, but really low down, starting from where it touches the mouse mat rising up for about a centimetre. I find this more comfortable and natural position of where your thumb and little finger would generally rest when you use a mouse (yes, have given it some thought!)
Looking at the modern mice thats out there, the thumb buttons are high up and above the natural 'thumb line' if you see what I mean...
Does anyone know of any mice where thumb button(s) are lower or am I alone on this one?

 

[-Aura-]

Nano, relax yer fingers as if you`re holding a ball and place it down on a table.

Now, twitch your thumb to the right.

Now, slightly (and I mean slightly) extend your thumb forward and to the right.

Now, press down on your index finger.

Now, move slightly to the right and do the same.

Now, curl your index finger up slightly and press down.

Now, do it a little more and press down.

Now, slightly more and press down.

Now, extend it fully and press down.

Now, use your middle finger and press down.

Remember, you must perform all of these tasks whilst pretending to hold a ball.

Do this many times and see if u get uncomfortable.

No? Then get an MX518

 

[reflux]

Thumb buttons on the Razer DeathAdder are quite low; lower than the ones on my Logitech G5 anyway (it's a similar shape to the 518).

 

[JTrickle]

Didnt take me long to get used to my 518. I then went back and used my old MS Intele on the 2nd computer, and it felt cheep and tacky.