I have the iFly version and really like it. I get steady frame rates at 35 (locked via external limiter) but if the mouse pointer becomes active in VC, frame rates tend to drop down to 30 or so. This is a quirk that quite a few people have had with this package. Some people have worse frame rate drops when the mouse pointer is active. No one seems to know why. I certainly can't figure it out. If it wasn't for this quirk, I would be perfectly happy with the airplane and would find no need in possibly looking at buying the PMDG version.
JOE---- Asus P8Z68- V Pro; CPU: Intel i7-2600K 3.4ghz OC'd 4.6Ghz,
8G Corsair Dominator DDR3-1600, EVGA GTX 580, Creative Fatal1ty
Champion Series sound card, 2 VelociRaptor HDDs for Win 7 64 and FSX, 27" Samsung Monitor