Travis,
I started using them a couple of seasons ago and wouldn't treestand hunt without them anymore. They are all not created equal however. I ordered both of the ones that 3 Rivers sells, one that's around $3.95 and the other is $8.95, I believe. The more expensive one is hands down the better choice especially for colder weather. It's called a Kwik Loc by Saunders if memory serves. The cheaper one is solid rubber and didn't function well for me in cold weather. The Kwik Loc has a metal spring steel insert that helps it function well in cold weather. I have never been of the opinion that "more expensive is always better" but in this case, it's true....