I have a first model Windrider, and after using it as my daypack on Kilimanjaro, it's become my goto commuter pack. I've been biking with it all over the Seattle area for close to 8 months now, and that includes carrying two cameras + light stand, umbrella, strobe & battery pack, and a few other miscellaneous items now and then. It's kept my gear dry in spite of some intense storms, and it's still holding up.
It shows more wear than my 4-year old McHale, which other than being dirty, doesn't look like it's seen any use at all, even though it's my expedition pack, which I take on all of my day hikes as well as backpacks, because of the photo gear.
Considering that the Windrider has had quite a bit of use, and I'm comparing to a full Dyneema custom pack that cost almost $1000 more than the Windrider, I think that speaks well of the Windrider.