I have the 5" model.
All in all it is a decent sander. A bit heavy, but it does sand aggressively and has variable speed. I find it makes my hands tired as the barrel is pretty large and I have large hands so if you do not I would say it would make your hands tired quicker. The dust collection hose on mine did not stay on very well so I put a tywrap on it to hold it tighter. It comes with a little velcro thingy as well to tie the power cord and vacuum hose together that I consider a must. Otherwise the vacuum hose ridges are always getting caught and hanging up on the side of your bench.
Thinking about it, I would probably pass on this one and look at the Bosch sander that looks similar to the Festool Rotex. Pricewise the Bosch is comparable to the Porter Cable, seems to have better integrated dust collection than the PC, and does both rotary and ROS sanding. Just my .02