Maybe you could get a demo board from TI for example with really nice converters, if not there are some around but depends on what you are looking for. There is a topic running in the truth table about some nice converters, I guess you should ask there of how it's going, they where working on the USB connection now, the converters where running for logic output, interface was missing last time I checked. I'm waiting there to came out for S/MUX ADAT I/O.
JS