I picked up a Flash 22 with the dividend sale and it is working well for me. I've had a chance to use it as luggage for a quick road trip and several hikes. After a 10 miler yesterday with essentials, cameras and water, I'm sold on it for my go-to day hiking pack.
Yesterday's load included a one liter bottle in one outside pocket and windshirt in the other, snacks and phone in the top pocket, and cameras, puffy and essentials in the main compartment, and there was plenty of room to spare.
The shoulder straps feel on the minimal side at first and trim smooth out and settle in. They need a little arranging as the thin design can wrap around while putting the pack on. Once smoothed out and adjusted they felt fine with the 10 pound load and that was over a simple base layer tee.
I don't use the waist strap and will probably remove it. That can be done without permanent surgery which is something I really appreciate in pack design.
The lid is permanently attached, by I like lid pockets. The strap on the lid helps the pack keep its shape. I did add a bungee cord array to the double rows of daisy chains and the lid trap helps to keep items stored there from getting away. I carry a z-seat sit pad there and it fits perfectly.
There is a removable foam pad that is a type of foam I haven't seen before-- rather dense stuff but it works well. A back pad is a good thing in small day packs to keep stuff from poking you in the back. The stiffness of this one contributes to the pack shape too. REI touts it as removable to use as a sit pad. That is possible, but not that easy or convenient, and the pad is rather small and not nearly as comfortable as my z-seat, so I'll stick with that.
I could pull off a SUL warm weather overnighter with this bag, using my Gatewood Cape, a Prolite short pad and a minimalist quilt. If you have thought about something like a GoLite Ion with pockets, just get this pack.