I can't recall having problems with betas except for memory issues on os x. Now, using CVS builds is an other matter, but beta builds are pretty safe. You can alway do a backup of your inomplete files folder if you fear loosing downloads.

Ciao

__________________
Liens d'intérêt /Links of interest:
Gnutellaforums en français /The House's rules you have to respect / First search the forum, then create a thread / Free software alternatives! - Logiciels alternatifs gratuits!/