I bought this mouse about a year ago seeing the potential of the second mouse scroll, sadly it was impeded with it's limited software. This day I saw that they had Logitech SetPoint 4.0, and my dream was realized.
The problem with the second scroll was that it was limited to "document flip" and "zoom", and in a gaming engine that equates to "crash the game" and "nothing". But with the new software the second scroll has all of the same options of the regular buttons, plus it gives the active scroll the option to act as a third button. which means: 14 button fully customizable mouse, with 1000+ dpi and laser technology.
This little change in software has transformed the ultimate office mouse into the ultimate gaming mouse, and with built in software detection you don't even have to chose.
So lets look at it from the bigger picture :
Tilting scroll (mouse scroll tilts left and right)
Active scroll (press down and it can switch scroll modes so you spin the scroll wheel and it keeps spinning, making for FAST scrolling)
Second mouse wheel (thumb wheel, NOW 100% CUSTOMIZABLE)
Basic 4th and 5th buttons
button behind regular mouse scroll
awesome precision.
And now you can pick this thing up for under 50$ on amazon! (I payed 100$ for it)
Plus it has a 10-day rechargeable battery, and a kickass display stand that matches my monitor and my DS lite, and my PS3 and my webcam...