I wrote this to a friend of mine, who just asked me for very similar advice. I cut out irrelevent parts for you.
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I think my Crumpler Sinking Barge, the Lowepro CompuRover AW, and Tamrac Adventure 9 were all around the same price. I chose the Crumpler because the "Customary Barge" allows me to get my camera vwithout taking off my backpack!!! With the Lowepro and Tamrac, you need to take off the backpack, place it on the ground or a table, unzip the camera compartment, and take your camera out. With my Crumpler, you can unzip it and get to your camera just by taking off one strap and swinging it around your body. No risk of the camera falling out due to the design. That's a HUGE convenience.
The quality of the Crumpler seems much better than the Tamrac or Lowepro, but my friend seems to enjoy the Tamrac. It's obvious once you touch the straps.
The Crumpler Customary Barge's camera compartment is smaller than the Tamrac's and Lowepros. For me, this is OK because I only intended on having a camera + 2 lenses. I think 2 lenses, or 1 mid sized lens + 2 small lenses is enough. With the Lowepro CompuRover and Tamrac Adventure 9, you can carry your camera plus another 4 medium-sized lenses or so.
As for the "general compartment", the Crumpler's is by far the most useful. It has a larger carrying capacity than the others, and can easily hold a jumper, sunscreen, sunglasses, map, small point & shoot camera, among other things. The Crumpler is also the only bag that can hold an A4-sized notebook, magazine, or paper of any sort without folding or rolling it. This is IMPOSSIBLE with the other 2 bags. I knew it would be a useful feature, but not this useful. Fantastic!
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Sooooo.....if you want a smaller "general" compartment and larger camera compartment, get the Lowepro or Tamrac. If you want a larger, more useful "general" compartment and don't mind a smaller camera compartment, get the Crumpler.
Between the Lowepro and Tamrac, I don't think it matters. The only REAL difference is that the Lowepro CompuRover can carry a tripod, while the Tamrac can't do it without a special add-on. Other than that, the most interesting feature is an all-weather (AW) cover.
No, really. It's not a really special, magical cover that's easier to put on, or protects the bag better than other AW covers. It just means the cover is included with the bag, and is stored in its own, "difficult to find" pocket. Don't let this be the deciding factor.
Get the bag you like most, and then buy an AW cover of your own, and put it in a pocket of any bag.
Remember, even a black garbage bag is more waterproof than most AW covers. Buy one from any outdoor store if you want a better cover.
Stupid site. Unreadable info. Seems pure hype, not pro.
I don't even know if that brand is available here.
Lowepro is all-weather.
Thanks.
Too bad. The quality of my Crumpler is better than the quality of the Lowepro and equivalent Tamrac that you're looking at. Oh well, continue on.