You should. It's a great show, and it's a shame it's taken this long for a proper DVD release. Shout Factory now has my undying love and support.
Certainly the Steve Purcell-penned episodes are the strongest ones, as I recall, but overall it's still great stuff. Even the attempts to kiddify it (like adding "The Geek") didn't really phase it all that much. The spirit of the humor was still intact.
I suppose the Telltale Games "documentary" probably does feel like an extended commercial, but since they're largely responsible for the resurrection of this franchise, I think I can live with it. It also helps that the games are really good. A new one's coming out this week. Great time to be a Sam & Max fan!
The only thing better would be an Adult Swim revival of the show. But Steve Purcell may not even be up for that at the moment, so I guess I can be content with the fact that he's working on the games. (He also works at Pixar.)