Given two copies of the same album, one ripped uing LAME 3.90.3 -alt-preset-standard, and another ripped using LAME 3.96 using cbr 192, which would you keep, and which would you delete? I'm just asking this because I'm pressed for hard disk space right now. Hope you respond to this trivial query! Thanks in advance!

keep lame 3.90.3 aps

If they're both transparent, delete the larger one.

Yes, of course, that would be the most optimal solution, but I just wanted to know if, at a whim (based on technology improvements), will the newer (albeit constant bitrate restricted) psy model used in 3.96 beat out the old 3.90 vbr one? File size differences netween the two albums' songs are surprisingly small for this particular album (lets just say no killer samples here, hehe).

I think the preset standard in 3.90.3 was very well tuned, comparable in terms of quality to V2 in newer Lames (just with the difference that the bitrate was higher), so I would keep Lame 3.90.3 APS.

I'd keep the 3.90.3 one. Not only is it VBR, that particular tuning (aps) must be the best tested Lame tuning ever. It was the recomended encoder and setting on HA for years.