I only ever played Episode 1: Amethyst Mountain. It was pretty cool, and I enjoyed it - but - it was kind of short-lived enjoyment.
The idea is really cool, and the game was well made, no doubt about it. The customization of the wolves is pretty nice in particular. Only problem was, it gave you a couple of goals to achieve, and then... that was it.
There wasn't anything else to do unless you wanted to just run around killing elk over and over. So it amused me for maybe an hour, and then I got bored and stopped playing.
There's probably more to do now that they have the second episode available plus the multiplayer thing (neither of which were available when I first found the game), so I'd say it's worth a try.