Meh.
It's not bad, but it's mostly moe of the same. If you liked Wii Sports, you will like this. If you didn't then you won't.
I figured it would be like that (I don't care for Wii Sports) but I bought 2 WM+ anyway just to complete my collection of games. I don't nmind spending a few bucks on hardware addons considering the games are free.