The Sheperd hook will last a long time. Not sure exactly how many times it has been hit but the hook has been hit a lot and has held up well. It has actually held up better than the post behind it. If it was going to be a permanent stand on a private range, I would go with the thicker fence post. I am sure you could get a couple of seasons out of it as long as you hit th target most of the time. It may only last one for me. Lol
I bought some targets from Bobcat Steel and decided to make "Gong" style frames. I took two old realator signs and welded them together to make an "A" Frame. Then used towing chain to hang from the top. It works really well.
Here's is complete quick and dirty hack job of a target stand that I did.
Basically, I took (2) 4"x4"x8' posts and dug them into the ground. Then I hammered (3) 2"x4"x8's across the two posts for holding steel and hanging targets. That was very simple, and gives me the foundation. Next I bought the steel targets from Wideners, some chain, 4" nails/spikes, stainless bolts for the plate to chain connection. I held the plates about right where I wanted it and eye ball measured it. Then I hammered a spike into the lower 2"x4". Then it was just a matter of trimming the chain to length with a pair of bolt cutters and bolting it to the plate. I've only had this setup for a short time, but it's held up to a lot of M855 punishment from short range and it's still doing just fine.
I bought some of those cheapo metal saw horse stands and they work great. Very light and portable, will take alot of hits (I need to replace them but ive used them for 3 years)