I've had my messenger bag since June or so, and I think it's awesome. I like the size for my 14" laptop, plus notebooks, plus music scores or textbooks, and with that all in there, I still have room leftover for my Pearl Izumi jacket and a hat.
In the main compartment there are 2 water bottle pockets that are open, very flat when they're not in use, and a good size for a Nalgene bottle, or I've also packed 1 shoe in each water bottle pocket so they don't get the rest of your **** dirty.
The outside pockets are good, too. I keep my u-lock and pump in the lock pocket, tire levers, a wrench, pens and blinkies in the small pen pockets, and in the zip pocket I keep my wallet, phone and iPod.
The outside is rugged and really waterproof, but it does seem to make me a little sweaty under the bag and the strap.
The strap though...the strap is AWESOME. Really comfortable, and it's got the carabiner on the front, so you don't have to **** up your hat or take off your helmet to put it on or take it off.
It's also held up really well, although the liner is kind of starting to crack around where the flap curves over the top of the main compartment.
Sorry for the novel. Definitely read the FGG review of it, too, that's pretty good.
Oh, also, the laptop sleeve is pretty burly on its own, and it's big enough for me to put my 14" iBook into a neoprene sleeve, then put in the Banjo Bros. laptop sleeve.
PM me if you want to know anything else.