I have the gas block scout mount on one of my Minis. I've never had any trouble from it. It holds it's zero very well. And it comes at a decent price.
A friend of mine has the SCAR stock on his AC. I love the stock, but it comes with some disadvantages. Compared to a standard wood or synthetic stock, it is extremely heavy. And at $550-$590 each, they are very costly. I'd like to have one, but I'm not going to pay a 500% premium for one over another stock.
Wyman