While i don't have a class A i do have an 02 with the 4speed auto. The 5star tune worked as advertised. My setup is at 17k lbs combined. Stock the X shifted short, it always seemed like it could go more rpm which i was doing manually. I have the 3 tunes eco. Towing and power. The towing tune works great, i got the tuner just for the better shift strategy. My towing mileage did go up slightly about .5 mpg. Everything on Mikes website is true he does not candy coat anything. Excellent customer service. If there is something you don't like about a particular part of the tune just call or email and he will change it and send you a new tune.
I highly recomend them!