There is a thread here where some are using the microsquirt to run ignition on one or both sides. There is nobody running the megasquirt for fuel that I've ever found. There have been a few discussions but nobody has posted about it.
I've only found people running SDS, System32, and (rarely) Motec. I don't know what the Honda conversions are running.
B&G themselves do not condone running the MS on aircraft.
The MS3 is a pretty well made product. I'd still be reluctant to run it as the primary ECU simply due to the lack of hours in the air. I'd consider running one with a proven secondary (SDS or System32).
Source is available, which is nice. I'd looked into stripping out all the non-relevant code and doing formal analysis on the rest but it's a lot of asm and a huge amount of work.
