If you have the money, most tuners will tell you Microtech is the best. Differences are only slight between alot of brands though, and it does come down to what will suit your application. In terms of auxillaries needed, different features etc.
Microtech does have a good customer support though, and are quick to help you out unlike some other EMS companies which can take a while. Talk to your tuner about what they reccomend or prefer to work on, this will most likely get you the best results
