Very poor fit - Trinity Force AR15 Upper Vise Block

The two pieces do not close around the upper receiver flush (on a very standard mil-spec S&W). There's an apparent warp in the pieces right out of the box, it has about a 3/8" gap/wiggle from top to bottom. I did put it in a vise then clamp the top portion with a C-clamp to squeeze the gap, and it just felt wrong so I did not proceed with a barrel nut change. Ended up borrowing a friend's more expensive block and it fit perfectly. Get what you pay for here, definitely better off spending more for a quality hinged type block, especially if you're going to be using it more than once or twice in your lifetime.