I have a lot of experience with MegaSquirt as well. I have built several of them and am currently running it on my 1981 Fiat Spider 2000 Turbo. It's a GREAT system for the do it yourselfer and it also forces you to really understand fuel injection. It has a great interface on the laptop and I even have mine set up with Bluetooth so I can tune wirelessly.
Options on the MegaSquirt v3 board with the MS-II daughter card are virtually endless. MegaSquirt does it all - Fuel management, spark control, timing control, PWM, idle control, etc. You can have multiple tables for different driving conditions and it logs EVERYTHING when you tell it to. I love it because I can tune it exactly how I want when I want and I don't have to wait for or buy a pre-programmed chip. Also there is no need for a MAF either since you can tell MegaSquirt to adjust fuel properties by either TPS sensor only or TPS with MAP sensor. The TPS with MAP control is a must on boosted engines. So is a wideband O2 sensor, such as the Innovate Motorsport LC-1. On my Fiat, I'm running with MegaSquirt v3 + MS-II daughter board, Ford EDIS (Electronic Distributorless Ignition System) with VR sensor at the crank (36-1 toothed crank wheel), and the Innovate Motorsport Wideband O2 system. This with the Garrett T3 turbo on it is a real hoot!
Personally, I love the idea of putting the MegaSquirt on the Turbo Buicks. But, again, I like them stock and I hate making wiring harnesses. Ugh!
Later,
Eric McCann
Germantown, WI