I had a P3 and had no issues. Just need to cross your t's and dot the i's when you set it up. Rega's don't have a ground wire.
IMO, the deal right now is the Anniversay P3, almost a P6 and cheaper. Use the saved money for a nice cart.
I would skip over the P6 and save up or get a used P8; you get the better arm!
All TT's are susceptible to footfalls.