I've got a Mont-Bell Peak Shell jacket that's great in every way but the very light (12D) fabric and DWR worries me for long trips with a backpack over it. In the short term, the straps could wear through the DWR before the trip is even over, causing it to wet-out. In the long term, the jacket may not last as long as I'd like.
A possible idea to counter-act this: WPB pads glued or stitched over the existing fabric at high-wear point. McNett makes a self-adhesive Gore-Tex Repair Kit with 5cm x 10cm Gore-Tex pads that you just iron on. Great, but too small for shoulder or waist pads. Anyone know of something very similar but larger I could use for this purpose?