Thanks for the reply. I shot a roll at 320 with a two-stop push and found too that the color balance did not shift any noticeable amount and that the grain increased only slightly. Due to the lighting I was shooting in (indoors under fluorescent lights and outdoors in snowy conditions), it's a little hard to determine the contrast increase, but it does not seem to be excessive. Perhaps that extra 1/3 stop of exposure helps keep the contrast in check.
I've only scanned one of the slides, but if anyone would like to see it, it's
here. (Yes, it's a rather unimpressive shot, I know.
) I'll try to shoot another roll under different conditions to get a better idea of how it reacts to pushing.