If the main things you're after only doing 2-3 night trips with a reasonably contained kit list, and you're main reasons for switching packs are to save weight and have a stash pocket on the back.. I'm not sure it's the right choice. There are lighter packs capable of carrying 2-3 nights of stuff, if you're keeping your total pack weigh under 14kg (which in most conditions is very doable on a 3 day trip). And the front stash pocket has divided opinions a fair bit. So, if the main needs are lighter, and more stash pocket storage, you might find other options more suitable.
The Zipper pocket is small and some think it's relatively useless (it would be a handy place to store a map and permits, if you were hiking in a place that needed permits). The shock cord closure means its only good for holding a wet shelter or maybe something like rain gear - which might be sufficient for you.
I had one briefly and sold it due to a fit issue. Basically the shoulder straps were too wide set for my body type (relatively narrow - i'm 58-60kg and around 5'10"). It seemed a really well made pack, with much higher end materials than anything else I've owned - and it was less expensive, which is impressive.
It seemed to transfer weight to the hips at higher loads better than other packs I've used at higher loads.
The feature set and layout is quite unique. Since it didn't fit well enough for me even to go for an overnight trip (pinched under my armpits), I didn't get a chance to figure out if I liked the unique pocket layout. Some people have complained about the small zippered shoulder straps for being too small. They'd be good if you carry a few dinky bits you want quick access to - such as chapstick, hand soap, etc - personally they'd probably have stayed empty for me. Some seem to be finding the side pocket thing a bit of a gimmick, as if you put much in the pocket above it, then you collapse the volume below - and vice-versa. My plan had been to store my camera in the "quick access" side pocket and my cold soak pot in pocket above, which I think would've worked and solved an issue with quick camera access I haven't managed with other packs.
Edit to be clear, I'm not bagging on this bag (hah), I think it's excellent value for the quality of build, and it's a thoughtful design. Just it's worth being conscious that it's unique features make it relatively specific in who it might or might not be optimal for (assuming it fit you)
