On my last two mountain bikes I had grip shift for my front derailleur and rapid fire for the rear. I couldn't use a rapid fire for the front because my hands are very small and I didn't have enough leverage with my thumb to get into the big ring. I personally didn't like the grip shift because I had to take my hand off the brake to shift.

On my current bike I have dual control levers (shift and brake with the same lever). I really like it. I have heard complaints from some people about this system, but it works for me. There must be enough complaints about them because Shimano has brought back the option of separate levers.

The nice thing about the 2007 XTR dual shifters over the 2006 is that now you can shift multiple gears in either up or down at once. It would be nice to "throw away" 2 shifts at a time.

I thought it would take a while to get used to a different shifting system, but after a few rides, it's second nature.