Every pit has its tweaks and methods. Kenny Rogers and I cook together and we did a couple comps with his Pitmaker trailer and honestly, what I noticed was that the tendency to overshoot ramp up temps comes from the lack of pre-heating. These are pretty conservative pits from what I have seen, providing you pre-heat the chamber and even the massive water pan. What Pitmaker showed Chad seemed to work fine, by stacking the lump/briquette in a daisy chain around the outside edge of the firebox, adding chunk into the chain and letting it do it's job.... we maintained temps fairly easily in the 250 range for the first couple racks of ribs we were playing around with.
I would be interested in a Fat Girl too, I just don't have enough information on them, nor have I seen any videos or enough detailed photos to determine the build quality and temp control, as I have seen with Pitmaker. They are built like tanks though, which is the primary draw for me. I don't want to have to trade up again someday, I want something built to last and their machines certainly are that.