I pretty much agree with what has been said, except for no water in pan. I like to use water when I cook ribs. Don't need it with butt, brisket, or chicken but I think the additional moisture helps keep the ribs from drying out, especially if you don't foil.
I use Royal Oak lump and a full ring will last for hours. Depends on cooking temperature and ambient temperature and wind. I don't mind a little overrun on the temp going up since it will fall pretty quick with several slabs of cold ribs hitting the grate.
Smooth Smoke BBQ Team, KCBS CBJ, 2-WSM, Cajun Bandit Conversion, wsm 2880, Smokey Joe Mini wsm, Old Country offset, several kettles.