Just installed the F700BT a couple weeks ago. Nice system. The touchscreen can be finicky though. Certain button locations (especially the upper right corner) are really hard to hit. Also, the unit is slow... slow to boot up, and slow to react to inputs. But honestly it has so many features I love it anyway.
The P8000BT might be a good choice if you don't care about the big screen. Not as flashy but cheaper, with physical controls, and not as attractive to potential thieves.
One thing about the F700BT - make sure you either perform a hardware bypass or hook up the handbrake cable properly. My brother didn't do either and now the unit thinks I'm never parked and thus it never enables certain features. Once I see my brother again this coming weekend, I'll get that fixed and finally have a fully functional head unit!
For more information on them look at avic411.com. Lots of helpful forums there.