I have no experience with them, but the intense stage 3, 4 is wicked loud from what I've seen in the videos. XPZ sounds more muscle like, which is why I'm probably going with that one, and I'd like to max out my m90 before I move onto other things. If I get an XPZ cam before you happen to get your new cam I'll let you know what it's like. I'm just being patient waiting for a used one for cheaper