Worth it if you can deal with the limitations - Sylvan Arms Gen5 LH Folding Stock Adaptor

I'll parrot what most of the other reviewers have said before, it does what is says on the label which is allowing you to make your AR a lot more compact. The build quality seems great, no weird burrs or issues with deploying or collapsing the stock. It is incredibly nice if you have an already short 9mm or .300 BLK rifle and want to fit it in a backpack or smaller piece of luggage while still keeping the upper on the receiver.

The one thing I will bring up is that there is a gap between the two halves of the adapter when closed that will let out a decent amount of gas if you're shooting suppressed and don't have a low back pressure can. I'm not sure if this issue is just with my unit or not but it does mean that if you want to mitigate it with an o-ring or gasket material you lose some of the utility of the folding hinge as you now have to retain another part that otherwise won't be retained by the system. Without a can this issue isn't quite as bad, just make sure you're wearing eye pro.

I didn't notice any lockup issues with it and I appreciate that the latch on the stock side of it seems to be replaceable in case you end up forcing it or snapping it off, you would probably have to contact Sylvan Arms in that case for a replacement however.