Sam & Max has good content, but a couple of issues.
First, it has framerate problems. It's pretty tolerable most of the time, except for a chase scene which is almost unbearable in episode 1. After that, it's smooth sailing.
Second, a lot of the dialogue gets recycled from one episode to the next. I spent episode 2 & 3 clicking on objects and talking to characters and getting the same dialogue as I got in episode 1. It was underwhelming. From episode 4 on they freshen up the dialogue and go to new locations, so like my previous quibble, you just have to move past it.
The third issue is just that most of the puzzles aren't too hard. There was about one tricky puzzle per episode, so if you're really after a brain tease, there are better puzzle games out there.
All that said, the game is definitely worth $30, IMO.