I have also found that USB capture devices (like the one mentioned above) do not work nearly as well as FireWire ones with Catalyst.

Also boxes like the one from Canopus can go as high as 1600x1200 resolution.

http://www.canopus.com/products/Twin...winPact100.php

BTW
Richard - how did your tests go with the Canopus Twin-Pact box?