I can't believe no one has mentioned EAC. If quality is the biggest concern, why would you consider any other ripper?

Funny, EAC is what I've used to make MP3's for the past year or two, I totally forgot that it can produce OGG files. Thanks for the reminder, DeadFire.

Of course, now that I know that 3.0 empeg is slated for FLAC support (thanks, tfabris), I still might need some other conversion tool.