When I use a vertical grip, I tend to wedge my support hand fingers into the space in front of it with my thumb wrapped over the top of the rail. I usually have very little of my hand actually on the vertical grip. I just use it to pull my hand against in order to draw the carbine into my shoulder pocket aggressively. This technique is hardly unique to me and we are starting to see gear, like the new Lanco Tactical Grip Strop, that supports the technique.
The Lanco Tactical Grip Stop brides the gap between a vertical grip and a hand stop. It is purposefully shaped to support more grips than a typical hand stop would. The user can slide their hand further forward like you typically would with a hand stop or wedge it into the curved front of the Grip Stop like you would with a vertical grip. The leading edge is textured to provide plenty of grip and bite into a barrier to stabilize the carbine when structure is available.
The Grip Stop is machined from aluminum right here in the USA. It is hard anodized black for durability and a low profile finish. It comes with all necessary mounting hardware and can be mounted on many of the most common hand guards on the market.
There are other hand stops on the market but none of them are quite like this. I think it looks like it has tremendous potential. Check out the Grip Stop at Lanco Tactical.