I use a EHS Racing programmer. I use it when I am running a stock motor, exhaust and when I run Big Gun Exhaust and a HC3 cam. I use differant setups for differant types of racing, it seems to work for me.
i have the EHS programmer, air box lid and velocity air filter and noticed a very minimal gain. but i will be getting a barkers exhaust soon and thats when you need the programmer, if you plan on leaving everything stock then id say spend your money else where