i use AP probably 90% of the time. point to where i want the exposure taken off of, depress half way, recompose and take the shot. only time i use manual is if the lighting condition is difficult, ie sunlight directly in front of the object, etc.
i use Exposure Compensation on certain lenses. i find with my 15mm Heliar, the auto exposure makes my pictures darker than i would like (guessing its something to do with the wide angle) so i up the exposure compensation a click or two.