Fit good - controls very stiff - SIG SAUER Stock, Mcx, Mpx, Sig Folding & Telescoping

Received in a surprisingly timely manner. The Picatinny attachment bracket is solid and accurate to 1913 specs.
The opened position does not have a lot of slop or play.
The controls are VERY stiff - I have good hand strength (paramedic for decades lifting cots) but the angle to push the stock extension button requires a specific angle and sometimes both hands. It does seem to be getting slightly looser as I break it in, can just use one hand now.
The fold open mechanism is to lift up on the stock at the Picatinny bracket and this pivot point/spring is exceptionally strong. There may be manufacturing tolerance issues, I'm not sure. I relubricated it which helped somewhat, but you have to hold it low on the gun side and pull hard on the other side to raise the back portion up enough to collapse it.
It does collapse to the left side of the gun, leaving the ejection port unobstructed, which is nice. I tried mine on a Kuna with a non-reciprocating bolt so I know it can be shot collapsed.
I recommend this item with the caveats above. I'll update this if it 'loosens up' more to the point of fairly easy manipulation of the extension and folding mechanics.
I didn't see the specs list the over all length but it is SHORT - puts your eye right at the back of the weapon's rear sight. Some may find this disconcerting, doesn't feel like a normal rifle setup - more compressed.