At least go try on a few other quality backpacks so you have some points of comparison for the Kelty.
BTW, Kelty gear has a reputation of being decidedly low-end and suboptimal. Mass-market, mostly crap. Mostly the same, but to a lesser extent, as The North Face. In terms of packs, the really quality brands are Osprey, Gregory, Granite Gear, GoLite, Arc'Teryx, and maybe a couple of others. EMS and REI brand are usually good too.
Not that it's bad gear. The pack you bought looks pretty good, if a bit old-fashioned and maybe a bit overengineered.