Not sure exactly what you are asking. Your stock ECU can be reflashed for free (well $91 for the cable from Tactrix) with different parameters, then there are companies like Turboxs, Element Tuning, Cobb, Vishnu, AEM, EcuTek, etc.. that all make excellent products. Most will agree for ease of use the cobb accessport is the cost effective route but if you are going for huge hp, you may be better suited with a Hydra from element or an AEM ECS. With the advent of speed density tuning of TurboXS's UTEC it is now better suited for large turbo's as well. Is there a single "Best" out there? Not really. Are you going to be doing your own tuning? If not, talk to your local tuners and have them recommend what they prefer to tune with (trust me, they'll have an opinion on this matter) it could very well be in your best interest to get the engine management that they recommend.