I have also been using the Alta Rise 33 messenger bag, which is an extremely well made bag designed to be carried on your shoulder for, in my opinion, primarily event or wedding photography or similar.
First of all the wide strap makes it an extremely comfortable bag to carry about. I had it on my shoulder for about 4 hours non-stop while shooting a wedding, and it was as comfortable if not more so than any bag I have ever worn on my shoulder.
Inside the bag there is one large main compartment in to which you fit an insert that is fully customisable to make the most of storage space, so that it is easy to reach your camera body or lens or flashes or whatever you choose to have in there.
At the wedding I was shooting I had it split into three compartments, one for my main lens and attached body, one for my flash and one for a spare lens. It also has a multitude of two or three zipped pockets that mold around the shape of the bag for keeping things like batteries and a notepad or similar. Like the Alta Rise rucksacks they have a zip that goes around the outside of the bag which when undone, expands the bag even larger so that you can fit even more equipment into it.
As with most messenger bags it has a large flap that Folds right over the top and down the front and attaches via Velcro and a clip, but right on the top of the bag when the flap is closed there is a zip so that you can easily access what is inside. I found this extremely useful when I needed to change lenses quickly or attach a flash.
All in all there isn’t much at fault with this bag, if anything. It is perfect for carrying lightweight kit or limited kit if you are on the move at an event, or if you don’t need to take much with you as it is a nice size to carry with you when you are travelling.
In conclusion I am a huge fan of the Alta Rise bags, both the rucksacks and the messenger bags. And I could well see myself buying a Rise rucksack in the near future.