I use the 91 octane Tow Street tune daily, and love it, although my throttle response at a gradual take-off is seeming to worsen (going to try a throttle reset procedure). Otherwise, no complaints. However, when I run my 91 octane Performance Street tune, and really get on it, like, to pass someone on the freeway, or get onto the freeway, etc., it more often than not will bog out. Unless I'm just driving normal, it doesn't feel trustworthy. In the past, I had an issue with it throwing a check engine light after this weird issue, and had found I had a broken spark plug-- but after replacing those, it still had this issue (bog or suddenly jolt). I don't know if I'm hitting a limiter, or what, but am curious if anyone else has ran into that with that particular tune.