I didn't read the whole thread, but I can share my experiences with
Audigy 2. Audigy 2 NX, actually, which is a USB-connected external
device. I recorded using this device, and the recording parameters
were set to 96kHz/24-bit (a 32-bit recording into Audition). The
frequency content of the recorded file proved that the sampling
ferquency was truly 96 kHz. But the real bit resolution was 16.