Hi Michael,
Realise you asked this question a while ago. I am currently running a project on XDCAM and cutting on an adrenaline. 1080i/50.
I have found there is little to no use for the proxy files as they look and sound terrible. I have therefore been importing the full res MXF files, editing with them at half resolution, and then transcoding the sequence to DNX185hd for the online. I have tried to import the variable frame rate footage into an interalaced project, but with no joy. I am however hoping that I can capture it using HDSDI out from the camera when it returns from a shoot.
Did you have any luck with this problem?
I look forward to hearing from you.
Best
Tom