Unless your using a light recoiling gun, both the hog saddle and the pig saddle will be poor for follow up shots.
The device actually clamps onto the gun at the balance point, so you can guess what recoil does to that setup.
And yes they do attach to a separate camera type tripod. You will find in the videos that the shooters use their off
side hand to hold down the tripod while shooting. I personaly wouldn't be wasting my money on them.
If you hunt from the same remote locations, consider building some small benches patterned after a cross leg picknic table and stash them there.
Build them at home, then disassemble them for packing to the location, then reassemble with bolts and a wrench. Kneeling height works well and will be more stable. About 20" wide and 3' long will work well. We have several of them stashed for more than 10 years at some of our spots.
If your not of the timid type, you can also do some site work by way of (ahem) pruning some (brush) with a chain saw, and using a small shovel or military entrenching tool to level a spot to shoot from. If there are nice flat rocks in the area gather up those and build a bench with them. Again, it need not be very high, kneeling height is enough. If you go to Montour County Rifles website home page, you will see one of his guns sitting on a stone bench. That's not a posed picture per se, it is located on one of his walk in hunting locations in the same area we hunt.