Yes, they are slick to use. I have an original Anderson treesling, purchased in 1984! When I first saw Jerry's woodpecker setup, I got one.
I have used grade 5 bolts, no problems, but I'm not biggie! Mostly use allen socket head 3/8", grade 8.
As for trees, I hunt mostly from Hackeberry, pignut hickory, and hard maple. They have alot of holes, over the years. Heck we have maple trees that are tapped for sap, for years.
This past December, I pulled bolts from a Hickory, that were in for over 5 years. Didn't think I could, used a small pair of vice grips, gave them a twist, pulled right out!
Get ya some!