I fly AFPD for aircraft and Phoenix for helis. I voted for Phoenix because it is, in my mind, the best I have tried for helis (what I do most of) and will be getting better very soon all round with the 1.04 upgrade. Phoenix customer support is BRILLIANT!!

Reflex is good but the company sucks at customer relations and the infamous red/white bars of doom.

I tried G3.5 and hated it for its consumption of processing power......bloatware. Fixed wing physics are mediocre and even AFPD has better heli physics.

Never tried FSOne - not likely to either.