My migration to Thunderbird is now complete. I mentioned earlier I was having an issue with importing HTML messages into Thunderbird, which turned out to be bug 3157. Matt Baerbock posted a solution for post-processing the imported mailboxes to correct the errors and display HTML mails correctly. It’s an excellent script (though rather slow), and now all my emails are displaying properly.
There was just one (very minor) snag with the script. It didn’t pick up messages with Eudora’s <x-rich></x-rich> schema. However, there was only one message in my entire set of mailboxes that used this, so it was a small problem that will hardly affect anyone.
All in all, I’m happy with Thunderbird. I just hope that bug 3157 will get fixed before 1.0 is released, hopefully sooner.