I live in S.E. Colorado. The ground here consists of broken up lime stone shale on top of solid lime stone shale. There is some top soil in places, but not much. The country is mostly vertical and side hills. There is no vehicle access to where I am fencing. Fencing here is very difficult, to say the least. In the past I have resorted to a hammer drill in places because I couldn't drive t-posts in any other way. I needed to do some more fencing and wasn't up to using my old slide pounder, it would be more work than I could handle.
When I found the Rhino I looked at all the videos but was still a bit skeptical, but I didn't really have any other choices, so I bought one.
So far I have put in about 50 posts and I couldn't be happier. I have had to move 1 or 2 because I hit solid rock but other than that all have gone in. I am driving 6' posts 2' in. I have had to settle for 18" on a couple because they hit a solid rock. This tool is amazing. Time will tell how well it will hold up but so far I have had no real problems.
A hint: If you get one don't overfill the gas tank and don't over tighten the gas cap. At first my unit would starve after a little post driving until I loosened the cap a bit. Snug is good enough.