The more I play the more I think this is pretty good. I think it has LOTS and LOTS of flaws for a 2d/2.5d Mario, but it has good and challenging level design that does a great job at ripping off older Mario without feeling like a rehash.
My biggest complaint is the idea of kicking you out of a level every time you die even if you have a checkpoint. The process of watching the kicked out animation, waking up, hitting A, getting back, and being back to playing takes like 10 seconds or slightly more. If you're going for the hidden coins/exits where you are going to die a lot this basically makes the game feel like it has a 10 sec loading time after every death which is completely distinguished mentally-challenged for a 2.5d platformer.
I also am just not a big fan of the physics and floatyness. I'm getting used to it, but I still slide around a bit more than I'd like. Also the controls are very senstive so you can sometimes accidently duck (this won't be an issue if you're using the d-pad) and go into a slide when you really really don't want to and you can sometimes accidently lift the remote a bit in a chaotic moment and then you'll do a jump spin suddenly out of nowhere which can be very bad.
The power ups and levels and animation are nice. The turn over mini-game is not as good as the SMB one.