I have several DBCs, which never faulted me, and some time ago tried an RCC for comparison. My one had an erratic behaveour with regards to the sound, which implied wrong sounds being played at startup or when trying to shoot, or a complete lockdown of the whole card when connecting everything: the sound card, which is ready-made in China (I found the chinese supplier site some time ago) has several inputs to trigger the sounds,but in my card some of them didn't work, some locked the system when connected.
After reporting it to Bill asking for some suggestions I was told that I would have received a replacement system. That happened at the beginning of september, and never got any replacement.
Another negative aspect it that the rx18 amplifier catches alot interference through the additional sound wire.