I'd venture to say almost all of them have been pumped and dumped...bitcoin had many (major) crashes. I posted before that most of those alts (either clones, pump and dumps, or scams) have all but faded away and we are still up to over 22k from about 500-1k in March with lots of innovation and community still behind it.

And stealthcoin: it's the opposite. Look at the max graph on mintpal. The trend is up.