It also comes down to your power goal and budget... if you are thinking of keeping the car for many years and want to get BIG power out of it eventually, its worth the few extra $$$ and getting a real good ECU cause then you will never need to change it... If your after max stock power and arnt going to keep the car more then a few years, find a cheap ECU & tune package eg. EMS stinger approx $1800 supply, fitted and tuned...
Cheers