Great purchase.
I want to comment only about the size, because I also couldn't understand if it's the size I wanted before I ordered (and because I have a Herschel and was looking for a standard backpack again). It's slightly smaller than the standard Herschel, but it's not one of the very small ones. I would say the standard size for such a backpack is probably around 45cm (this one is 41). The main difference you'll notice is in the capacity. I don't think it fits a large laptop, and it might barely fit a change of clothes, for example.
Even though it turned out a bit smaller than I would have liked, I don't regret it at all; it seems very convenient for everyday use.
If you are, like me, used to having a backpack for anything, for weekends, for work, laptop, etc., this one is a bit small. If you want it only for everyday use, maybe with a small laptop, I find it excellent. Unlike the larger size, it is narrower and won't be a complete mess if you fill it up.
Ps: The way the magnets work is perfect, you don't need to ever worry of getting pickpocketed.

Update: I've been using it every day for 9 months now, I absolutely love it and it will probably last for a very long time.