Many thanks all for the good suggestions!
Reubent and Bongofury-
Are you referring to the Who's "deluxe editions" (2001 MCA) versions of Live at Leeds & Who's Next, or to earlier ones? Amazon reviews leave it unclear which are the good ones... my 1996 Quadrophenia CD(s) are sonically a bummer, so I'm hoping you mean the more recent releases. Are both LAL and Who's Next equally good (in sound quality)?
As a separate note, someone (maybe not this thread) recommended the RCA Living Stereo classical stuff... I second that for at least the Heifetz- the SACD Hybrids are cheap and amazingly good sound quality.