I see a lot of people on the forums posting that 320 CBR should be the preferred listening format, assuming you don't want to use FLAC/WAV/Other lossless. When I read about this I always wonder why people choose 320 CBR over other "better" formats, such as the various Lame V# presets. I'm not going to get too much into transparency, so for the sake of things I'll just compare 320 to V0.
For those unaware of what V0 is, V0 is the highest preset you can choose from the Lame encoder for variable bit rate mp3. It's largely considered the "smartest" of choices due to it's transparency as well as reduced file size in comparison to CBR rips, there's a reason why it's the most popularly downloaded format on any private torrenting site, aside from 320 CBR on electronic sites but that's for another reason. Now why is V0 better than 320? Here's some comparisons:
-Both are mp3, so they can both be used on every single audio players you'll use.
-Both are transparent, meaning aside from the rare few who can hear frequencies above 20k, then you can not and will not notice a difference between this and FLAC/Wav/Other lossless.
-Both are capable of reaching 320kbps.
That's about where the similarities end though. V0 surpasses 320 in everything else. The V0 preset allows the music to reach 320kbps, but only when needed. For instance, that song you're listening to with 30 second of silence? With 320 CBR you're getting 320kbps of silence, which is completely unnecessary, it simply wastes space. With V0 it dynamically changes the kbps of the song depending on how complex the actual sounds coming through are, so you're not wasting space on 320kbps silence, where it may go to 128kbps.
To give another view, think of it like this: Wav=320 CBR, Flac=V0. Wav is a constant 1,411kbps stream, like 320 CBR is a constant 320kbps stream. Flac is the exact same information bit for bit of the Wav, but compresses it smartly to allow it to dip below 1,411kbps, much like V0 does.
Keep in mind though, lossy to lossy transcodes are bad. Transcoding a 320 CBR, or any other lossy format (mp3, ogg, aac, etc) to a better or worse preset will cause artifacts and lost information each time, degrading the music regardless. The only music that should be transcoded are lossless formats, like Flac/Wav, to mp3/aac/ogg.
I hope that makes sense, I'm very tired but I would love to hear other's rebuttals.