I recently purchased the Skareb 40 size M so this is slightly larger then the small and I found the sizing to be just fine. I suggest is you have questions about your sizing specific issues go with the M instead of the L.
One of the problems I did find though was pics. I must have looked at over 10 different sites plus the North Face and could only find the basic same 3 images for the and the Skareb 55 (the bigger brother of this pack). For me this was solved very quickly by the staff. The gearhead I talked to online in the chat had a buddy in the warehouse who also had this pack.. and a digital camera. He was so kind as to take several shots of the pack my choice, then emailed them personally!
That is what made or broke the order for me. The super service. But alas I got screwed in the end and charged double shipping for me international order and had to pay double customs!
As for the pack well the 40 size M for me is enough I pack out pretty light but would be hard pressed for a tent and food. This is a hostel goers dream though!

Me and my girlfriend just bought 2 of these for fun. They actually zip together making one big space. Super light and soft we are using one right now on the bed for summer sheets.
The bag is a little tight though and flimsy. I would imagine day after day of stuffing this would render the bag useless in a few months. Though maybe another small sac would do the trick!
Also comes with a spot pre-stiched for a pillow ohhh ahhh he don't knock it ever had you pillow taken in the night!