audioman,
i've personally never auditioned the built in DAC of the B100. but one thing compared to the BDA-1 is for sure: the B 100's digital inputs 'only' accept up to 108 khz!!! playing 176 khz or 192 khz through the B100 is not possible.
the BDA-1 can easily handle these high resolution rates and is therefore the perfect match for the BDP-1 if you want to playback high resolution files!
i don't know if a squeezebox is able to playback up to 192/24 files?
al.