I'd love to have a collection as big as theirs.. omg. That's what I call hardcore fans. xD
I may be a big H!P fan, I don't buy that much of their stuff. I have like, 6 MM CDs? Plus I still listen to tons of other artists as you can see in my last.fm profile.
Oh and what's wrong with Berryz? They may be young but their stuff is extremely catchy. They're not that young actually.. the oldest is only one year younger than I am xD