Every Puzzle has a Solution.
Professor Layton has one of the greatest honors of being one of the few games I play when I'm not playing it. Oftentimes you'll come across a particularly difficult puzzle (one of the extra ones frequently), and after staring at it for quite some time either leave it for later or set the game aside. Of course, it's never far from thought, and you'll likely find that puzzle creeping into your brain over the next day or two till you finally stumble onto the solution.
The storyline is, in my opinion, not terribly deep persay. If you give it a little thought you'll solve most of the mysteries presented on your own. But, that's not really why you're playing the game, and it doesn't bother you much with how interesting the characters are and with how well the story is fleshed out. It very much feels like a whimsical family setting, and would have likely felt right at home being produced by Studio Gibli. The voice acting is especially superb where it is available, Professor Layton and his assistant both match their parts perfectly and help flesh out the characters.
The puzzles range from the simple to the obscure, to the time consuming, which all work fine since they never let you settle into a proper or boring rythym, you're also never more than a few seconds from being able to save your game, so it's friendly for bustrips or any other unknown amount of time. Anyone who uses their portable for actual portable gaming should definitely give this game a chance.