the expresscard 34 slot

is there any documentation out there to indicate that Ki pro users will be forced to use sony's SxS cards? what about a workaround that includes some cheap SDHC card(s) enclosed in an expresscard 34 adapter? Obviously, the SDHC cards are substantially cheaper than sony's 32gig SxS card. I'm gonna take a a guess here in that SDHC does not hape the proper transfer speed to record HQ ProRes media to it. I like the idea of having a couple SxS cards in addition to a handful of detachable drives for the Ki Pro.

One idea to go along with that is to see if the Ki pro could simultaneously record low-res proxy files to the SxS card while recording ProRes to the hard disk. Then again, all that media management back n forth may not be worth the headache