SACDs only output from the analog outputs OR from the HDMI output of the XA5400ES.
you read it right: SACDs don't work with DACs and you'll need 2 inputs if you want to use a DAC (you can buy a box that will add inputs to solve that one).
others will no doubt disagree, but SACDs just aren't the huge dramatic improvement that they were supposed to be. regular CDs, it turns out, are quite capable of sounding very good, assuming they're recorded/mastered well.
if you really want to listen to a lot of SACDs and have the upgrade bug, you might want to look at getting a SACD player that is known for excellent CD playback - there are quite a few out there and some can be had used for the price of a good DAC (about $1K).
AFAIK, there are no stand-alone HDMI-input DACs. The only ones are inside processors.
I wonder if it is not an economic issue as licensing and qualifying to HDMI might be a significant burden, especially for a small specialist company. In addition, these same companies are the ones who complain about jitter and other issues with HDMI.
Note, however, that there will be an Ayre universal player with HDMI output and that it will implement Audio Rate Control to resolve the jitter issue. OTOH, Ayre is not (yet?) planning to offer a DAC or preamp that you can plug this into.