Smooth and easy tune for the M157
I was interested in a tune that would give a nice boost in performance without adding mechanical stress that would result in significantly lower reliability. RENNtech has the reputation for quality that I trust and also saw that the tune was suitable for the 91 octane fuel available in my State. The HHT was very simple to use and the instructional video was clear. Total time to complete the tune (including hooking up a trickle charger just in case) was well under 10 minutes. I still recommend reading through the concise use manual since it included tips about the temporary engine codes that would have concerned me if I wasn't anticipating them. I took my wagon out for a spin on the same route before and after the tune and noticed a significant and smooth power gain throughout the RPM range. Not sure if it's my imagination, but the exhaust note also sounded better. Although I've only had the tune installed for 2 weeks, I'm happy with the purchase so far. Looking forward to putting many more miles on with the added power!