I've never had any personal experience with any MS systems, but everyone I know who has used one seems to love it. I've always been curious as to why more Ford folks don't use Megasquirt? My best guess is people are scared off by the complexity of having to install it themselves (or the price of having someone do it for them). From what I've heard it is really not that much more expensive than buying an xcal, prp, different mass air meter, mafia etc...If you don't mind me asking, any idea on how much you spent converting the car?
I've been running MS2 Extra on my turbo Probe GT for about 6 months. I built the unit, wiring harness and did the base configuration/tune myself. I had a friend with more experience get it fine tuned for me. I run it as a full standalone, my original ECU is sitting on a shelf in my shop.