You know, I was thinking of making a thread about the Mana series.
Except I was gonna call it: "Final Fantasy Adventure: The Only Good Mana Game?"
I need to try Legend of Mana first before I do that, though I've not heard good things...
Its all a matter of personal taste of course but in general I enjoyed each game up until Children of mana, and despite various issues I have with Dawn there are a few things I felt that it did well.
To my knowledge Adventure, Secret, Secret 2, and Legend are all mostly regarded as atleast good games. After that you get a fairly large range of opinions on the rest of the games in the series.
One of the things that I really lived about legend of mana in particular is how non-linear it was (especially for its time) you can play the game from start to finish however you choose due to the way the artifact system works. Combine that with a fairly nice variety in setting up your character, the fantastic art direction, and great music all mixed to make a game that I always really enjoyed.
There are people who enjoy a more structured "go here, do this" approach though so it's certainly nor for everyone, but how many games can really claim that?