I own the Lemhi and it is a great pack. Carries everything I need for the day elk hunting here in Montana. The Lemhi is a little trimmer pack and more of a panel loader, with a zippered main compartment opening. It is also about 1300-1400 cubic inches smaller. The Elk Hunter has a top pouch flap covering the opening to the main compartment.
All Bison Gear packs are extremely well made and will last for a long, long time.
It depends on what your intended use is, as to which model would be best for you. As a daypack, I think I would find the size of the Elk Hunter too large for my taste. I like a little narrower pack that is more "behind me", to clear brush and tree limbs.
Hope this helps. Good luck on the search!
Ron