I have an Easton Fullbore 3600 that I like quite a bit. I think it retails for like $170, but I got a deal off of camofire for like $100.

It expands from 1200 to 5600 cu in. I use it as a day pack and then if I get something I expand it out to the 5600 cu in pack. It has a lightweight internal frame that I like.

There is no question that an external frame pack is better if everything else is equal for hauling meat. But I like to take out a bunch during my first hike out after a kill. Everything has held up well on my pack so far (3 hunting seasons/1 dead deer/1 dead elk).

For my first season, my shoulders would really hurt after a day of hunting. But then I realized I had to tighten the waist strap better. After that, I haven't had problems. That's something that someone with more backpacking experience would have known already.