I hope the Mackers M6 gets a commercial release. I'm dying to hear it but I can never secure a copy easily, especially when it comes as a disc with the BBC magazine.
I'm dying to hear it because I've heard Mackers' M5 and found it to be simply one of the greatest versions of that work ever recorded. The Liverpool orchestra play with enormous gusto and verve and the brass section is amazing. Mackerras, too, proportions the work perfectly, giving us a longer-than-usual first part to highlight the music's darkness and wildness, a fleet, bubbly scherzo with a fine solo horn, a beautifully shaded, songful Adagietto and finally a finale that bubbles with rhythmic and contrapuntal alacrity.
As of now this great M5 is only available in Mackerras' Icon box or the big EMI Eminence box, i.e. it's no longer available individually. Thankfully I found a cheap copy of the now deleted Classics for Pleasure individual disc. His Mahler 1 was less special though it bore similar merits with this M5. I look forward to hearing his 6th although I doubt I ever will.
Regarding the Andante-Scherzo or Scherzo-Andante matter, I suppose since both ways are "valid", what I prefer depends on the performance of the Finale. I think a performance with a very long finale (eg. Sinopoli, Bernstein, Tennstedt, Barbirolli) would be better off with a S-A order since the Andante should serve as a focal point to balance the stylistically similar first part (1st mvt and Scherzo) and the weighty Finale. If it were played in the A-S order the latter part (Scherzo and Finale) would be way too weighty to balance the first movement. That is why I always prefer playing the Barbirolli in the S-A order despite Barb's performance practice. However if the performance sports a fast and furious finale (Solti, Kubelik, Kondrashin), the order should be A-S to retain the weight proportions of the first and second parts with the Andante as the focal point. Just my opinion.