Strategy to migrate from StarTeam 5 to Subversion?

Question

I need to migrate a large project from StarTeam 5 to Subversion, and I'd like to keep snapshots of (at least) 5-10 of the major releases. I've considered the following:

• Manual or scripted export/import of each snapshot. Advantages: straightforward, easy to select labeled/dated versions. Disadvantages: time-consuming, does not preserve comments.
• Polarion offers what seems to be the perfect tool in svnimporter, but it requires a .jar file from StarTeam 8.0 that is not present in StarTeam 5. Advantages: automated, complete. Disadvantages: requires upgrade to StarTeam 8.0 for one-time use.
• Migrate via some intermediate repository (e.g. StarTeam -> CVS -> Subversion). I haven't yet found any intermediary that will cooperate with StarTeam.
• Migrate only the latest source. Advantages: simple, fast, encourages developers to invent new solutions rather than repeating history. Disadvantage: encourages developers to invent new solutions rather than repeating history. :-)

I'd appreciate any experiences or suggestions you might offer. Thank you.

Answer 1

You can run a Star Team server for an evaluation period (30 days?) without requiring additional licensing from Borland - this would give you plenty of time to run a few practice runs, and give you a complete, reliable solution. Well worth the effort.

Also, don't underestimate the value of retaining your source history.

Updated Nov 6: One project that I'm involved with has used the Polarion tool to migrate a single StarTeam project into SVN. Took a little bit of work, but the end result is flawless. Well worth the time investment.