Well, it is a solid suppressor. There are better, and worse. We are Rex dealers, and enjoy working with the owner. We have never heard a compliant, but I think people also know they are buying into an average suppressor. Then again, everyone does not need the best of the best, or will put more money into glass than world class quiet. When you move to subsonic, it doesn't take a world class suppressor to make it go hush-hush either.
Not many suppressors are true hearing safe unless you are using subsonic rounds. For that mix of guns, I would recommend multiple suppressors. I am not sure if you are looking for a one-size fits all, but there is a big gap from .30 cal to .45 cal and 9mm in the middle. I have seen a number of people use the 9mm size on a .300 BLK, but the MG7 is pretty wide for a standard 9mm pistol. I would not recommend it. It will work well with a sub gun.
If we can help you in your decision, DM me.