P3D V4 and 64 bit looks and sounds like it is great, but I am honestly not even interested in changing sims again.  It has taken me a year or more to get P3D V3 setup and most addons downloaded and working.  In the time I have used P3D V3 I have had about 2 OOMs, so 64 bit isn't a necessity for me right now.

Sims I am using (in order of most use):

P3D V3
DCS World
FSX:SE
Aerofly FS2

I may just wait for P3D V5 before I jump ship again.