I have used both the Harris and the Stoney Point "Pole Cat" sticks. I like both, but for different situations. I only own the smaller Harris bipod, which makes it really nice to use for shooting off the bench or prone for long range groundhogs. I use the sticks for hunting deer (and some groundhogs) since it's a lot easier for me (visibility-wise) to shoot from a standing or sitting position.
In my opinion, I prefer the versatility of the shooting sticks...you can adjust them from the sitting to standing position quite easily, and it is not attached to your gun. Good solid rest as well. The Harris is nice, but I have it attached to a stud in my forearm, so when it's on, it's always there. Probably more of a solid rest than the pole cat, but less versatile.
Whatever you decide, if you go with the Harris, just make sure that you use a swivel stud in the forearm, NOT the universal barrel adapter.