I used some of this drill stem to make fence posts 40 years ago. It is still as good as it was then. Some of the fence has been removed, some is staying, most was never cut for posts. I pierced the posts for 3/4" smooth rod, put the 9'8" long posts on 9' centers, 4, 5, and 6 rods. I should have enough for 1500' of fence. These make heavy posts Not a project for the average home owner.
65-90 lengths 4.5"OD X .435" wall 28'-30' long, $125 each, I believe it is just over a trailer load.
25-30 posts cut, pierced, that have been in the ground, corners, "T", line, 5 and 6 run, $55 each.
More than enough 3/4" smooth rod, $0.36 per foot in quantity.