The best of the Mario%Luigi series.
Having Bowser not only playable, but playable for half the game was a very smart move. Because Mario and Luigi have no new moves whatsoever. The graphics are very appealing although we haven't quite switched to full 3D yet, and it made great use of the DS's touch screen. While the second game made no use of the touch screen at all. It was as if Nintendo forgot that the bottom screen could be used as a touch screen.
Anyway, this game gets a 9 out of 10 from me. There are no flaws at all. Just a few inconveniences which are so small that I can't remember any of them. And yes, I got the game recently and played it every day since then. So far I've put around 25 hours into it, and I'm not quite finished yet.