2O2S, we have a brick gate, and have a 6" pipe on the gate hinge side, and IIRC, we sank it 4' deep, with concrete. It's held up well. I think our pad for the brick columns is 8".
I agree with Bill. If you can, add electricity.
I replaced our old gate opener with a Mighty Mule this last spring. I started having circuit board issues after a few months, and got with MM's phone support. Outstanding real-human customer service, and I had a new circuit board on it's way that same day.
I got the 20' model for our 14' steel gate, and it handles the weight well.
