Kelty is pretty much a commodity pack, it's fine for lugging around books. The only Kelty I've owned had an 11 month life span before a seam blew out.
Living in Colorado, I'm pretty tough on packs. I tend to overload them, smash them into rocks, drop them down steep inclines, and dare my dog to get the biscuits out herself.
I just had a pack made this spring by Dan McHale.
McHale Custom Packs
The pack was overpriced. Dan is the crankiest perfectionist I've ever dealt with. The fitting process and lead time suck; but the fit and construction of the pack are phenomenal. Mine has a Spectra cloth bottom, with Spectra ripstop pack fabric.
While I don't generally get shot at, I do put myself into situations where equipment failure has serious consequences. I've trashed a lot of packs, I expect this one will outlive me.
Kifaru and Mystery River are also worth looking into. I opted for McHale because he could best accommodate my camera.