I'm definitely not an expert, but in my obviously biased opinion, my brisket is pretty darn good. I cook mine slow and low until it reaches 202-207. I use lots of salt and pepper for rub, and I use the larger rock salt type salt. Also, the thinner portions of the brisket are always going to be on the dry side, although they should be pretty tender. Also, when you slice it, make sure you are cutting as close to perpendicular across the grain as you can.

I've got a weber smokey mountain charcoal smoker and a GMG pellet smoker. I prefer the flavor of charcoal, and I think the added moisture in the weber may keep the meat more moist, but it is hard to beat the ease and cleanup of the pellet smokers.