I've had them take less time but never longer.
Ditto. I've had them come in at 55 min/lb up to 1.5 hours (mostly I seem to hit around 1.25/lb give or take 5 min).
You can foil if you wish; it's not mandatory and many people don't. I do if, like Nick I want lots of juices to build a sauce from. Sometimes I'm working a different sauce angle so I don't. I am not one who feels that foiling makes brisket pot roast-y. I think it can
, perhaps, if lots of liquid is used and the heat is high, or if allowed to cook to long in the liquid.