i use an ms1 with msextra code for the larger fuel and ignition tables and the engine turns 8,500 and runs perfect.
on my camaro i use a megasquirt 2 with ms2 extra code and see no real difference except the ms2 extra has slightly larger fuel/ign tables
if u want resolution with the ms1 use the ms11 extra code and use table switching based on map sensor value this gives u 2x the resolution
cheapest way to get an ms2 setup is to buy a used ms1 v3.0 and then buy the ms2 cpu which plugs right in
or u can take the ms1 v3.0 or 3.57 and buy the ms3 cpu and that also plugs right in with only a few jumper changes needed
btw the ms cpus are faster then the popular 7730 749 and other gm ecm's alot of ppl use, ms2 and above is faster then the latest and greatest lsx ecms that everyone loves and some of those power 1,500-2,000 hp engines