Mackerras is the "gold standard" in this piece, not just because of his unflinchingly exciting conducting, but also because of his carefully edited version of the score which gets as close as possible to Janacek's original, and very effectively fills in those few spots that Janacek didn't quite complete before he died (the laughing chorus in Act 2, for example). The Supraphon recording is also very good, particularly for the cast (Novak, Pribyl, Horacek, Blachut, Zidek, Berman), and of course the Czech Phil under Neumann. It is still available.
There's also a live concert version featuring Kubelik/NYPO which I had hoped would be issued on the orchestra's own label, but it wasn't to be. Listeners interested in hearing the corrupt, "triumphant" ending should sample the suite (two or three versions available) which features the closing march earlier on and turns the final "freedom" chorus into a radiant apotheosis quite contrary to Janacek's intentions--but as a concert piece it's rather nice. There is also, IIRC, an earlier recording using the old, pre-Kubelik/Mackerras score that I heard years ago, possibly when I was working in the Supraphon archives in Prague.
Dave H