Where is the double-occupancy?

Actually, I find it a shame to have to return them.
- Ergonomics is super for my rather small hand.
- The mouse wheel is Logitech typical perfect.
- The wireless connection is (compared to my MX Revolution) really great, obowohl the dongle is plugged in behind 2 screens under my desk behind my PC.
- The processing is clean.
- The materials handy, yet pleasant.
- The driver leaves many settings for Windows 8 to what is super ... aaaaaaber ...

... I can prove by double no button more. At every Logitech mouse that I had could set a key double, and that was so far my 7!
- For battery life I can not say anything because I unfortunately have to return the mouse because of the lack of double-occupancy.
- What I think is a pity the missing middle mouse button (which had MMN best solved with the revolution that the wheel turns freely, depending on the speed or geraster is)
- In addition, I noticed that the cursor with me a slight train has left if I hochbewege the mouse. I can not quite explain, but I suspect that this is due to the slightly different shape of the mouse compared to my previous MX Revolution and I therefore consider somewhat obliquely. Very very funny.

So who can do without the double-occupancy, with a lot of Windows 8 (and the special features) works and a grippy, rather small mouse is the right place, and should try it once
However, for me it's nothing.