I'm putting a 45' privacy fence between myself and my neighbor's house.
I plan on 6 to 7ft post spacing. Cost is an issue (I'm footing the bill), but I don't want to sacrifice strength.
I've done the 2 3/8 galvanized steel posts on a small 16' fence between the garage and house. It's super strong (24+" in the ground).
I've read about the OZ post anchors (the T4-850). A friend had good luck with them here in SE TX. We get a lot of clay in the ground.
It's a little cheaper with the anchors, and certainly less work (which is time/money for me) to avoid an auger and mixing (set time too).
The fence will terminate with a post. There won't be a gate attached to the end post. In fact, a separate steel post will be there for an iron driveway gate. So, the fence will just support its own length.