go for cheapest.. probably PowerFC
HOWEVER, Haltech has about 1000000000x more features:
- flex fuel
- launch control
- anti lag
- flat shifting
- boost control
- internal map sensor, ditch AFM
- closed loop knock, wideband O2, etc.
- IAT input
- no need for stupid data logit boxes, direct USB
I personally would go Haltech, not bother with those dim sim Plenums and use the stock one.. afterall you're only using a high flow, which does not warrant a plenum upgrade.. save that money for a proper mechanic diff.