[Lucifer]

I’ve heard that the MM2 is good on the CM871, but I’ve also heard it’s bad according to other people’s.
What’s the truth out there?

If I were you I’d look over what is being changed in that overlay file and make a decision for yourself. You could also strike up a conversation with the creator, Rawze. I don’t think he’s on this forum but he has his own forum. 

I personally haven’t seen a problem in the later versions. Earlier versions tricked a sensor which wasn’t the best method.

I couldn't have answered better myself. MM2 isn't bad provided your using the latest version on the correct engine.