@skyjedi: The resolution of Vista-vision is about twice that of a normal 35mm frame but it's quite irrelevant, because I'm pretty sure the finished effects only exist on 35mm anamorphic.

@mfm: I would personally consider that good enough but I also think, that today 4K is pretty much the standard and with their resources, it wouldn't be much more expensive than 2K, so 4K should therefore be used, even if they are scanning an IP - even theatrical prints benefit from 4K scanning, so an IP certainly would.