I have 31 medals thus far. While it's kinda annoying to do some feats, it's pretty fun, though most of the time I complete a feat without realizing it, so I find Mr. Medal pretty creepy. Heck, everyone in the Medal Office (or whatever it's called, too lazy to look up the actual name) is pretty creepy. It's as if they really rely on you collecting all the medals out there as if the world would be destroyed if you didn't. Or at least their company. It's so odd. Kinda reminds me of the creepy ubiquitous reports they have about you, even before you start your journey.
I also have a feeling I'm never going to finish collecting all the medals since some of it deals with wireless, and I don't exactly know how to work it out, if I have wireless to begin with.