What are your thoughts on JOINT STEREO vs. STEREO?

I was ripping --alt preset standard but just noticed that it ripped to JOINT STEREO rather than STEREO.

If the same sound is to play in both channels, joint stereo stores the "sound" once and "remembers" to play it in both channels rather than storing the same "sound" twice.

I think STEREO may preserve some quality over JOINT STEREO.

Weather I'd notice it on my equipment is questionable.

I ran a test with two CD's and found the total file size difference between the 2-albums worth of MP3 files in JOINT STEREO and STEREO form was 6MB.

--alt preset standard also uses VBR-OLD style.

I can select VBR-Default which is a combination of the OLD and NEW form, set quality to Normal (q=5) and VBR Quality stays at VBR 2 as it would be with --alt preset standard. I set mode to STEREO with Bitrate Min 128kbps and Max 320kbps.

If --alt preset standard sets Quality to q=5 then I think I'm gianing a little quality without giving up much space with using VBR Default over --alt preset standard.