When I was looking for yet another bag, I found the Tamrac's aesthetic appeal, along with good workmanship and quality materials, to be an enticing combination, although due to my arm/shoulder injury, apart from walking around in the house to test it out, it has remained unused.
The bag has thick padded shoulder straps, padded back, and chest / waist straps which all make for the expedition look. I think its ideal for backpacking / hiking trips, but might be a bit large for walking around the city, and though deeper than some bags, isn't unwieldy plus it meets an airlines carry on requirements.
To test it in the house I loaded the bag with a Canon 50D plus battery grip and added several long length lenses, UWA plus macro lens, flashgun and a small laptop in the front padded compartment etc which it swallowed with ease. It felt surprisingly light to me and well supported across my back, the pads on the back of the rucksack have an air gap in between them which will allow any excess sweat to escape. This means that your back should stay dry if you are on a long hike.
Strengths: Large capacity, lots of divider panels (they are quite rigid); deep enough for a pro model camera or body with battery grip and a very long lens. Lots of pockets, compartments and accessory attachment points, the 2 wing pockets on the rear are good for CF cards / small accessories as you do not have to open the main compartment. If you need extra storage, the optional packs attach to the main bag through loops placed around the body and straps. You slip the attachment straps under the backpacks loops and they clip back to the packs via a snap button and Velcro.
Despite its camera/lens devouring dimensions, it's a very comfortable bag to carry due to an excellent ergonomic design. Straps are contoured and well padded, and the top handle is nicely padded as well. The tripod attachment system is functional, a shorter tripod with four-section legs might suit this size bag better to avoid it poking significantly over the top of the bag.
Weaknesses: Some of the zips appeared a little stiff to operate, but this could be due its newness (or my weak arm) and they may loosen up after use. The main zip also has a rain flap that can be pulled over to protect the zip, but can then get in the way of the zip and some of the toggles.
But this is a very minor point and does not detract from the Tamrac Expedition 5 being a very functional and comfortable bag to use. Just wish I could.
Hope this helps.