Yes, to all of the above.
I have P3Dv2 and FSX both installed. I'm glad I took the leap and purchased P3Dv2. It's fun to have the option of simulators, wherever possible.
P3Dv2 really is a good simulator with some advantages over FSX. Minor bugs, but it's an evolving product. Their patch is due in a few weeks, so some bugs should go away.
I do a lot of comparison flying in non-Orbx areas. (I have FTX Global, FTX Vector and Pilot's 2010 mesh in both simulators)
P3Dv2 loads faster (the game itself and the flight) has dynamic shadowing, runs smoother than FSX, and I get better frame rates. This could be due to the very limited scenery that can be added at this time.
It's a semi-close call, but I still prefer FSX. Something about the coloring/texturing in P3Dv2 is different. They should be identical because of FTX Global, but they aren't. Also, it could be the $$ and time I have invested in FSX.
Re-installing all of the RTMM sceneries would (will) be a chore in itself.