To clear up my Ipad statement above: I had heard that via an SW update Apple had blocked the USB digital output capability that had been previously possible via the camera kit on Gen1's.
Comparison to Apple Airport Express which to my understanding is limited to 44.1/16 due to its architecture does not impress me that much.
The Pure I20 had best be sounding quite a bit better to justify its existence.
There's an article here that might make you more impressed with 16-bit music rather than be bought into all the marketing claims about 24-bit music for consumers. Just sharing...