Excellent Mouse with its own problems
OK.... I got this delivered today and tried for whole day... The impressions were like this..





If you have time.. then keep on reading. I will try to give as much details as I can.

First thing first, forget about innovations and features, this thing looks sexy. Logitech has set the mouse design standard so high with this one that it will make other manufacturers job a lil more difficult.

After getting it out of the pack I started using it. OMG.. this thing is heavier than the normal mice. I realized that my hand was avoiding the mouse and using keyboard more. Anyways, lets do the hard work. By this time, I already checked amazon return policies once.

Even after doing extra hardwork, I found that all the features mentioned on that site and the box doesn't work. This means I have to install some software. They call it SetPoint. I personally dont prefer any application just to get the mouse work. My machine is already overloaded and now this. But once I downloaded and installed the application (also included in companion CD) I got everything worked.
Hyper-fast scrolling
This is really hyper fast. Actually the scrolling works in two modes. One the normal scrolling where we feel breaks between scrolling and other one is this hyper fast scrolling. This scrolls like a wheel. Actually you can just start it with pressure and leave it to keep scrolling. I never scrolled 20000 line of codes top to bottom using scroll wheel earlier. And now, its just one scroll and done.
SmartShift™ technology
I doubt if its really smart. This is actually some logic (which I dont think devs at Logitech implemented it correctly) to switch between normal and hyper scrolling. It hardly wark the way I want it. But hey you can always switch manually by pressing the scroll wheel.
Rest all features are standard for high end mice like this which has multiple configurable buttons.
Finally, afte using it for a day I feel more comfortable with this. I mean this is the same thing happened when I bought Shure noice cancelling ear buds ( multiple models range from $100 to $500.. yes its $500) and felt pain in my ear canal before I got used to them. I think I will enjoy this mouse in long run. It fits so well in your hand that you hate using others after this. Its just matter of some time.

I hope this info can help you guys on deciding for this nice device. Should you want some specific info, shoot a Q in post.
Enjoy!