I have been using the same Kelty aluminum external frame and Boy Scouts Camper pack bag for the bast eight years. The bag has one main pocket and three small pockets. It holds about 2942 cubic inches.
This pack has served me well. I have trimmed down my load when hiking so that I have extra room in my pack on almost every trip. Now, I think I am ready to make a little change. I am seriously considering getting a Duluth Pack.
I mostly go on weekend hikes in the summer. Occasionally I will take a winter hike or a week long summer hike, but that isn't too often. I also canoe quite a bit. With my frame pack I could lash my sleeping bag on the outside and have all the room in my pack bag for other equipment. With a soft packsack I would need extra room to store my sleeping gear inside the bag. I have been using a pair of wool blankets more often now, and they do take up less room in the summer, so I don't know just how much more room I will need. The two packs I am looking at are the Duluth Pack No 2 and the Duluth Cruiser No 2.
The Duluth Pack has leather straps and a tump line. It holds 3970 cubic inches. This is an envelope stype pack, just two pieces of canvas sewn together. The pros of this pack are; it holds about 25% more than my current pack, it has a tumpline to take the place of the hip belt on my current pack, and it costs $105. The main disadvantage is that it measures 24" wide, that might be akward to carry through the woods, although I am a pretty big guy.
The Duluth cruiser is a box shaped pack. It holds 3280 cubic inches, but has no tump line. This pack costs $85. I feel a tump line is necisairy for heavy packing if the pack doesn't have a hip belt. The narrow width, 19". This means it will go through the brush easier. This pack is also larger than my curret bag. I am afraid that the lack of a tumpline will make this pack more difficult to carry. I have occasionally carried my frame pack without a belt, and it wasn't fun. A tumpline would be nice. Also, if I need to bushwack and take a small pack with, I have a packbasket that would be fine as a daypack.
I think I am leaning more towards the classic Duluth No 2. Pack. I can always use my packbasket if I want to take a day hike or bushwack where a big pack would be a hazard. For $20 more I might as well get more room and a tumpline.