The Prism AD2 will output two sample rates at once. I run a pitch and catch instance of Sequoia. I've done the test. On most things it's hard to tell the difference. I have two Prism DA2's so it was a pretty good test.
Your comments are pretty typical of the majority of high end
converters, there really isn't much difference at any sample rate...
Multiple sample rates is a nice feature, and so easy to implement, I wonder why more manufacturers don't do it?
Same with master clocks which output several rates but are from the same master crystal, so the playback and record setups (to use the hetero terminology, not that there's anything wrong
with that), don't drift...