This whole thing of using extra money and effort trying to capture that extra resulotion is really a futile excise of lots of wastes for absolutely no gain. If you read dvinfo.net you would have noticed there has been LOTS of discussions of using BM card, even with HV20. In a most recent thread (http://www.dvinfo.net/conf/showthread.php?t=89578
) somebody tested the resolutions coming out HDMI and component recorded in realtime vs the that of HDV, and the conclusion was that there was no difference.
And that's something to be expected, the resolutions coming out these HD cam (less than 650x650) are still far away from the HDV limit of 1440x1080. To me there is no point of getting a 1920x1080 matrix to hold signals coming out optical path and CMOS sensor with much less than 1440x1080 resolution.