I've used both, although I don't use either regularly or extensively, so my opinions are based on limited experience.
I have not noticed any issue with pivoting from recoil with the Reaper grip with either a 260 Rem or a 300WM with a break. My use has been mostly with one or two shot usage; I can't say whether this would hold true for shooting long strings or using rifles with more recoil than the ones I've used.
I like the Hog saddle clamp better, although I think Reaper clamp is more versatile. For my use, I like the straight walls better than the ones that curve over. The straight walls may not grip as securely, or work with as many shapes, but it's easier to get the rifle out quickly when you want to. I think the Reaper clamp will hold wider stocks than the Hog saddle.
I like the Reaper base and adjusting/control arm better than having a separate ball head, but it would be better if it had a leveler. In circumstances where quick leveling is important, the ball head is better. If you have an already level base or have time to set the tripod up so it is level, I like the Reaper base better.
I'm not sure about the manufacturing.