in addition to taping shows, I also use the HD-P2 to transfer a lot of Phish DATs. on the R500 DAT deck that I'm using, the coax out is a bit flakey, so I use the AES output. however, I'm not just using a XLR > RCA cable, I have a Canare impedance tranformer to go from the 110 ohms to 75 ohms.
it works great, and if you were planning on doing this consistently, I'd also recommend that you get a transformer to avoid an impedance mismatch.