All I can say is night and day difference way better than my ZZP PCM. I read on here about Will's tuning and decided to make the switch. There were afew bumps with my PCM but Will made good of the situation. It was well worth the wait in my opinion. I have an 05 Monte SS and when I got my ZZP PCM it was VERY sluggish. I did have to send it back to them too and after getting it back still had problems with ZZP. The transmission settings with the ZZP PCM sucked BIG TIME. Will's tune made it feel like a different car and it pulls really well now. Wish I went with OverKill the first time but his PCM's were locked at first. Either way I'm happy with my OverKill PCM.... GREAT JOB WILL
