The best bang for the buck seems to be the Holley Commander 950, no provisions for SFI with anything more than 4 cylinders, but the windows based programming is nice and the features it has is pretty good.
Haltech was always a favorite of mine, especially when they introduced the E11, being full SFI and sequential ignition capable on engines up to 6 cylinders, either as full sequential for more cylinders. The price didn't seem too bad either, much less than a sequential FAST system.
Why are you looking at using aftermarket engine managment? If you invest a little bit of time doing the research the OEM ECM can be made to work VERY well.
Ive had 20 chips made by Ben with the size of the cam and low idle I keep getting codes the map sensor is not acting properly o2 sensor TPS IAC all of them arre not responding well. Ive tried the stock chip Hypertech Chip and all to no success Ben is the best but I still have no way of fine tuning A/F ratio bounces between 12-17. Also anytime I make a change then the chip has got to be done again. Just for info all sensors have been checked with OHM meters and they are all good.