Because of the Performance Manager for the 737NGX, I've been able to squeeze a little more FPS out of FSX. It's just my opinion (I hope others will say the same), but PLEASE keep features like that available for future aircraft!

Well, I can't imagine PMDG would go backwards for future developments, although I cannot speak for them. Their history seems to show that when they create a new system for something, it carries over into later products.