I don't think i could answer Greg Goodson's question better than Greg Goodson could. Just like Chuck Norris could no more be better than Chuck Norris than he could have a better beard than Chuck Norris.

Really the HDPE frame is similar to most packs that have plastic frame sheets. The difference with Granite Gear is how they utlize the foams. The idea is not to separate the different components of a pack (ie. frame vs. pack body vs. shoulder straps vs. waist belt, etc.), but to have them all work together. This is critical with Granite Gear. As you check out most of their packs you will notice the compression systems and the way the waist belt, shoulder straps, and back panel meld into each other. This is the case with the Vapor Trail. Granite Gear uses two densities of foam in the waistbelt and shoulder straps. They also use two types of foam in the backpanel (fiber foam and EVA). This foam is the best money can buy and gives the pack structure and load carrying capabilities, but still keeps the weight down. Compression is key as is durability and you'll notice that all of the webbing is sown into 220D Cordura, not the sil-nylon. This webbing is critical in making sure the load is compressed to the body, or center of mass. You should notice that Granite Gear doesn't use lumbar pads either. Instead the waistbelt is very substantial for a 2lb pack and the HDPE framesheet/foam backpanel comforms completely to the back. Rather than having all of the weight centered on the lumbar region, it's distributed throughout the back keeping pressure points to a minimum. The Vapor Trail is able to carry up to 30lbs (a lot of weight for an ultralighter) and, with this recommended weight, you get an incredibly comfortable pack. The materials are also well thoughtout, especially the Schoeller w/ Nanotech backpanel material. This is the real stuff, the exact material that $220 pants are made out of. It's very abrasion resistant, stretchy, and dries super fast. All the materials on the pack are either Schoeller or Cordura. Hope that helps...______________________________________Wow, thanks for the great response, Jason. I just ordered this pack... your answer to my questions certainly helped. I have several packs with internal frames, several frameless ultra-light packs (SMD, Gossamer Gear), but I am really interested in seeing how this one compares - much appreciated.