At the risk of teaching grandmother how to suck eggs, FLAC is a pretty cool format but is a lossless way to rip CDs so there's no loss of quality. Audiophiles tend to use this format and usually have expensive audio hardware and lots of storage space as it creates large files.
If you don't have the expensive audio hardware I doubt you would be able to hear any difference in quality between FLAC and one of the lossy formats like ogg/mp3. The lossy formats create much smaller files. I would rip one track in various formats at various levels of quality then listen and compare before deciding which one is right for you.
If you really want FLAC then you'll need more storage like an external USB drive.
Those tiny green pcs just ooze cool and when my desktop pc gives up the ghost I will probably replace it with one of those, especially since a lot of distros now include arm versions.
Cheers, Martin
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