I have used both wood and steel. These are my observations. The wooden posts tend to heave out of the ground. They don't come out they just move more in the spring time than the steel ones do. I didn't drive any. I augered and cement/tamped all of them so far. For the corner posts (3"), and the first ones off of the corners (also 3") get a couple of bags of cement. I "H" brace them together, and brace diagonally to the first line post. For the line posts (2-3/8") I just tamp and mix in a half of a bag of cement. I know of a guy that installs chain link fencing, and he drives the steel ones with a Rhino post driver, and says he can drive 100 or more in a day(2 guys). I have never witnessed this, and would be impressed to see it. I Think that galvanized steel would last the longest. I have bought reject galvanized fence post last year for just over a $1 a foot. They were 2-3/8" od x .109 wall x 21' (I cut them in half and used 8' chain link fence). When I checked I think that non galvanized drill pipe would cost around the same, but it would be heavier wall thickness.They make twist clips for these post also. I have smashed my thumb more times than I would ever admit trying to drive staples into round wooden posts ( I know,I know, Hire a professional).