We used vss2svn with few problems, it just took a few attempts to get it right. If I remember correctly I ended up using a slightly old version as the latest seemed to have more problems. The mailing list was still active and helpful.
> 6.0 to SVN 1.7.5 migration
> Could you please suggest best migration tool for VSS 6.0 to
> SVN 1.7.5 migration - which maintains version history, labels
> and comments.
> I have tried dowloading & installing VSS2SVN,
> svnimporter.exe, vssmigrate,etc., Either the setup is
> corrupted or some fail to intialize and I am not able to find
> the right tool.
> Awaiting your response.
> Thanks & regards,
> Bhushan Jogi