The amount of bugs in KDE-4.2 was not very high. I have used it exclusively as my desktop and I DID NOT ENCOUNTER ANY BUGS I COULD NOT WORK AROUND EASILY. Many bugs were just minor annoyances, many of which have been fixed in KDE-4.3.
So calling that "criminal" is just bull-shit. Are you using kubuntu by any chance? Then the reason for your experience maybe packaging errors. Just use Debian.