My favorite thing about this bag is how comfortable it is. I prefer sling bags but they can get uncomfortable when you start loading them down with more than just a kit lens. This waist straps do a nice job of moving the weight down to the waist when you're just walking around and not digging through the bag. The waist straps could do with some padding (similar to the simple velcro piece on the shoulder strap to pad it against your ribs).
The design of the inside takes a minute to get used to (especially if you're used to a bag where each lens gets its own top loading compartment. In my bag, for example, I have three compartments (3 columns if you're looking at the side opening facing up). Each compartment is divided into 1, 2 or 3 section. There are velcro dividers between each. So... to get to everything you have to go through the top and/or middle levels. This means you put your less frequently used stuff towards the bottom and the more frequently used items at the top. After 6 months of using it this way, I have to say that it seems to work pretty well, and is more organized than I had first thought it would be. My biggest complaint is really the fact that they don't give you enough dividers and I had to scavenge some from my old bag.
The tripod attachment on the outside isn't great. I'm sure it stays in while you're walking around and such but if you bump it or set the bag down without taking it out first, the leg thats in the tripod pouch gets knocked out and best-case scenario it swings freely on your back and its annoying, worst-case it falls gets scratched and banged up. The little snap that holds the upper part tight against the bag is too wide and makes it tough to get it nice and snug without a ton of effort.
If I had the choice again, I would still pick this bag. Even with all its faults it still holds all my gear nicely and safely, has a nice big flat pocket in front for my bounce and flash mounted lightbox, looks professional and its comfy to use. I would pick this one over the smaller version only because this one gives you some room to grow if you ever think you might buy more gear down the road.