I have found that with the extra Coin Rush stages, as soon as I beat them I never play them again, unless they have a lot of coins when I was trying to reach one million coins. Is this the same case with you?
After I beat the tough one in the first pack, I made that my StreetPass challenge so that people would have to go through the hell I went though to beat it. And so they would have to buy it to beat it. My StreetPass challenge is the tough one on the first pack, no Tanooki tail, with about 100 something coins. What's yours?