I'm rocking a quest as well. I have one of the newer ones (thinner drum), EricS probes (BT/MET), and a black drum. I've been using batch sizes of 250g, though I like the idea of adjusting it such that I get 8oz of roasted coffee. Charge temps depend on the coffee, somewhere around 400F (BT) for standard profiles. For naturals and other super-fruity coffee's I've had good results with dragging out drying (subsequently spending less time in development) so I'll charge a bit lower, maybe ~350. I make many fan adjustments as roasts progress, monkey-turning knobs to try and keep BT on track and keep MET at reasonable values, so I don't have any hard advices there.
Been having a lot of fun with it. And fortunately there seems to be no shortage of quest experts scattered about the various coffee fora.