Fairly prone to cracking, but then most 90's alloy frames are. Bottom bracket and chain stay area are the worst culprits I think. Great bikes though, had mine 9 months and love it.
Forks differ depending on model. Ones with rigid forks are generally 1 1/8th and easy to swap. Ones with Headshok or lefty can be fitted with a reducer header to run normal forks. I like my Headshok but getting a good one is hit or miss.
Lots of info at http://www.vintagecannondale.com
If you're coming to the Glentress meet in a few weeks you can have a look at mine, I think that's what I'm bringing anyway. Have a search for the story of mine in readers rides.viewtopic.php?f=6&t=215248
'97 GT STS 2 - XTR'd to the hilt.
'94 Retrodale Delta V