Having been to both a couple of pop recording sessions and a classical one (can't speak to jazz recordings, they might be different), I can say that you likely will never really hear the finished product in the studio while the musicians are playing (they may be around for the mixing, but I'm talking about while playing their instruments and singing). A lot of stopping and starting with orchestras, and plenty of overdubbing and signal manipulation on the pop side (and some classical, like DG). I'm sure some purist recording companies do it differently, but I'm talking about mainstream stuff here. I think it would be instructive to be with the producer as he/she makes the final product, with the artist's input, to hear what the recording is intended to sound like when I hear it on my system, but personally, in answer to your question I'd say neither, I'd rather hear a live performance in concert by the artist.