depends a lot on what you intend to run, power, etc.
I had a 11lb tank (lite cylinder recall) which I liked because it was compact. I now have a 17lb ragasco. Most trips I supply the propane, small group size 6-10 peeps. We usually have a second tank so we can run both a burner and the stove without having to swap tanks ...
you will need a larger tank for colder weather heating (mr Heater) or for longer trips or larger groups. For simple overnights I recharge a couple of the smaller 1lb tanks ... Never done a Grand trip but would probably want two tanks unless it was summer time ...
Really like the ability to gauge the amt of stuff in the tank like I can on the fiberglass tanks