I use the Initial Ascent IK4. It definitely doesn't suck. It's the only pack I've owned, and I've used it on one western backpacking hunt.
Pro's:
Very comfortable, doesn't rub me raw anywhere.
Large lumbar pad.
Quiet, no squeaks.
Lightweight, carbon fiber frame.
I think it's 4800 ish cubic inches, which was large enough to hold 6 days worth of food/gear for our elk hunt.
I've hauled out several quartered out whitetails in this pack, but no elk yet, so I can't say how it will do on that end of it, but with 50-60lbs of gear loaded in it, it's very easy and comfy.
Initial Ascent customer service is awesome.
Made in USA.
Load lifters pull the pack nice and close to my back and transfers the weight to my hips.
It has a sort of hook on the top corners or the frame, which is great to sling a rifle, bow, or quarters onto.
Cons:
I wish it had a water bladder sleeve in the bag. I had my mother add it for me.
The stretch pockets on the sides & front are too thin, and stretch out without bouncing back. (This is on the older models, and the new models have an improved fabric I believe).
Love this pack, would buy it again