I had an 88 security, didn't like it. That's not to disparage what it is, but it's an aluminium receiver, fixed mag capacity (IE, no extensions), and just overall feels cheap. I got rid of it in a month (and up-graded to a Benelli Super Nova... but that's a story for another day). I had no performance issues, in the 150-200 rds I put thru it, mind.
Just got the Grizz last week, and in my opinion, is far superior. All steel, and feels beefy. Both the Mav and the Grizz fill the same backpack niche for me, but I have far more confidence in the Grizz.
My $0.02.