I know I'm late to the conversation but the Bounty 4500 is an awesome pack. I just bought one and the first time out with it was to help a friend pack his bull out. I had some bruises on my hips the next day and the last .5 mile the pack started hurting my hips, but it was 3.29 miles one way with an estimated 120 pounds. So given distance and weight, I think the pack did really well. You aren't going to find a pack for any amount of money that doesn't give you a little discomfort with that much weight after that much distance in my opinion.
The main compartment is just a big bag with a small pouch for the water bladder and that's it. The small day pack has three compartments with several pouches inside each, so it organizes really well. Like Timberland said, there's allot of straps to secure the load which is really nice. The blood cleaned out of the pack really easily too, if that's a concern. Coming off of a steep, snow covered mountain, I fell numerous times. There is only one very small scuff mark on the pack as a result and no signs of anything being stressed after the load out, so I think the quality is there.
All in all, I think the pack did awesome and I would recommend it as I haven't had any buyers remorse yet.