I have the Hypertech MAX energy. I think it has been very good for my truck and what my intentions are. It allows for speedometer calibration through changing gear ratios and changing sizes of tires. It provides the ability for you to change shift points from a -500rpm to a +500 rpm with 100 rpm increments with 1st to 2nd, 2nd to 3rd, and 3rd to 4th gear so you can see what shift point works best for each shift. Also, you can increase shift firmness so it shifts gears a little quicker under hard acceleration. You can raise the rev limiter to 6500 rpm or back it down to 5500 rpm and change the top speed limiter anywhere I think from 81mph to 186mph. There are always new updates online that you can just download to the tuner and you can choose to tune it for regular unleadead or premium unleaded.