srp is a very good all in one which does a good job on its own but you can finish off with their extra gloss protection if required, its quite easy to apply as its like water but very good. Its designed to work with srp so is the best choice in my opinion.
i used to use auto glym all the time, but i binned all I had when i found meguiars.
I had an impreza and the first time i clayed it (unfortunately it did take 5hrs in all...), i used one of their waxes - can't remember which one, but it wasn't expensive - and after that, a wash and re-wax every 3months or so and it always looked clean