Though I can't deny my entirely subjective attachment to the original recordings, it is indeed lovely to hear the orchestrations and harmonies with all the actors singing on pitch.
As much as I loved them, Alison Frazier tended to sing flat; while Stephen Bogardus sang so sharp I never was able to figure out the melodies to his songs. (These are intonation issues; I'm not suggesting they can't hear the correct pitch. Frazier did the vocal arrangements for IN TROUSERS and MARCH, IIRC, so obviously she knows something about music.)
It's probably not a surprise that I like Block and Rannells better, at least as recorded.
Christian Borle sang his role more effortlessly than any Marvin I've heard. Perhaps not coincidentally, on download he sounds like a supporting character in his own play. It's a beautiful sound, but Michael Rupert sang the part as if each performance were his last.
These quibbles aside, I am very, very happy to have this recording. We have to plan ahead to play it because each repeat is followed by 15-30 minutes of sobbing at my house. But this recording will get a lot of use nonetheless.