So I finally got to play this game and overall I liked it.
I personally don't like slippery movement in games but it wasn't a major turn off for me in this one although I did get annoyed by it from time to time.
The game's upgrade system took some getting used to but the overall gameplay was quite nice and it had some decent platforming challenges. Boss fights were great too, and while I was expecting a darker story, the plot seemed quite good and self contained.
One boss fight I had trouble with the first time I did it were the Sisters, but on my 2nd try where I figured their pattern, I managed to beat them with ease.
For that matter, if anyone would like to chime in with some story tidbits, feel free to do so :P
I did not get the best ending however as I only got the normal ending, but I can see myself going back to playing it again in the future.
The game's music is great and listening to it made going through the game and areas less tedious.
One thing I found a little odd though was the localization: The English is fine but it seems like a cleaned up literal translation of the Japanese text which made some lines come off odd and could've been presented more properly.
I don't own any Ninty systems but I wouldn't mind someday trying out the 3D ver. of the game.