The bad thing about My Nintendo is that Gold coins can only be obtained by buying digital stuff. So if you're like me and prefer to buy physically, there's no reward for it.
Other than that I like it more, Gold coins are redeemed automatically, and the others just scroll down or look for the Missions. No big deal.
Castlevania Judgment FC: 1161 - 3389 - 1512
3DS Friend Code: 3480-2746-6289
Wii Friend Code: 4268-9719-1932-3069