This pack is fairly small. Gregory sells it as an advernture racing pack. I've seen it at REI. For a little more money, you could get a bigger pack from Granite Gear that doesn't weigh a whole lot more and would be a more versatile choice for weekend and longer trips, or get one of Gregory's bigger packs.

The main thing before buying a pack is to gather all of your gear for a typical trip, take it down to where ever you are shopping and see if it fits in the pack you are looking at and equally important, that the pack fits you-not all of them will.

Buy a pack that holds your gear and fits you, instead of buying a pack then trying to fit everything into it.

If you can't get to a store and are buying online, buy from someone like REI that will take back whatever you buy, no questions asked. Otherwise, you may find youself stuck with something that is too small or doesn't fit right.
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Don't get me started, you know how I get.