Opera 9.5 Note
 

98 Opera Users considering an upgrade should note the posts and
problems at http://my.opera.com/community/forums/forum.dml?id=26

Users should keep their earlier system intact, as many people
have found the upgrade unusable.

9.50 looks like a respository of lessons on how not to do an
upgrade.

If you upgrade and upgrade your mail, you can't go back, unless
you have a backup, but then you could lose interim mail.