[NoDOHC]

I have experience with all ECUs mentioned except for Microtech. They are all basically the same when it comes to the basics. Each has a fuel injection duration and ignition timing map that it references based on engine RPM and load (as measured by a MAP sensor, MAF sensor, AFM, or TPS). The available features or adjustments vary widely, but for your first system, simple is better.

Basically, aftermarket EFI is only as good as the time you spend learning about it and the time you spend tuning it.

Dyno tuning is necessary for peak power because the car is either speeding really bad or revving so fast that you can't even get an idea what the AFR is. Dyno tuning for driveabiliy is unnecessary and actually more difficult than tuning while driving.

If I were you, I would learn the Megasquirt with your turbo sitting safely on your bench in the garage. That way you will not hurt the engine when you make a mistake (which you will).

The driveability will be mostly the same with or without the turbo, and the vacuum map will be identical. Really all you will need to tune is the boosted part of the map when you install your turbo (after you are comfortable with the software and your wiring).