What do you think is the best 20 liter...
What do you think is the best 20 liter pack
Best is subjective.
Ask a more specific question get a more specific answer.
This is certainly a nice "freeride"ish pack (more robust, heavier). As already stated this pack takes a lot for a 20 liter pack, and it still carries well when you stuff it and additionally put skis on.
If you're looking into a lightweight rando-race/trailrunning alternative, Deuter, Dynafit, CAMP and the likes have nice alternatives. Just don't try carrying your 100mm+ skis. They are not built for that.
That's only the brands I've been using, though.