I've got news for ya. RED has been writing 4K RAW video to CF for 5 years. It was fast enough 5 years ago, and it certainly hasn't slowed down.
>But Geez where was Sony with their new introductions. And how >about the video manufacturers. If we are all going to go with >4K video, and we will, we need some modern recording media, >and CF and CFFast are not it. CF is end of life (already at >its highest speed limit) and CFFast contains pins - yuck!