I like the Bags Connection Enduro model that I bought from Twisted Throttle.
It mounts securely (one strap around the head tube and one on either side that loops around the frame). It's easy to get out of the way for fueling (just unclip the side strap on one side and flop it over). It expands so you can ride with it big or small as needed. It has a waterproof liner sack. It has a map pocket on top, and small pockets on three sides (the back pocket is perfect size for glasses case). It's made well. It fits the tanK. In fact, I can't think of anything I don't like about it.