Another option is to just buy the ICU and get a climbing pack which you can open from both sides. I personally use a Dakine and can't really complain (got it for free, otherwise I'd be using the stated recommendation). But once again, f-stops are unbeatabe if you can afford them.
I have F-Stop's Tilopa BC, and I use it for everything: BC skiing for the day or up to a weekend, and with general trips I can fit everything I need for a few days in it. I have the Large ICU which makes the pack keep it's form, but you can fill it with clothes or food if you don't bring all your camera gear, taking advantage of partitions. It's straps compress everything down nicely when it's not completely full, but is probably on the larger side if you only want it for cruising around town for the day. Lastly, I've flown all over with the thing and have never had any problems whatsoever carrying it on.
I personally have a Satori and Loka(for stobes) with an ICU and I can fit the majority of my setup in there. Have some issues with the Satori not fitting in carry on mostly on small planes. Love them both but I am considering switching my main pack to Clik because of the major weight I carry (30-50lbs) and the shape of the pack and the side entry as well. I know a bunch of people who use both and you can't go wrong with either.