Legend of Mana was fun at times, and I liked the stories, but I was unable to finish some of the plotlines because they were so obscured.
The combat was a moderately fun Final Fight style, which was sometimes acceptable, but there was little challenge. A fight where one of us died consisted of the other hiding until the first revived.
It had a good set of concepts for creature and item buliding, but they were too complex and required too many rare random drops or fruits and vegetables (particularly weapons).
It was an ok game in many respects, but it was an abomination to the Seiken Densetsu style.
Sword of Mana was rushed and unpolished. It contained a few too many Legend of Mana elements, but it was at least a true Seiken Densetsu, if not one of the best.
Of course, each game in the series has been flawed in some way, but I love the series dearly, especially Secret of Mana.