I would assume the realtime effects they boast about the card is for Final Cut Pro only. That means realtime playback without rendering which is different than the definition of real time playback in a color corrector which would be the ability to make changes as the clip plays back in real time. After effects does neither, everything is rendered for playback unless you hit the space bar which is an approximate framerate that’s dependent on possessing power.
I color correct in FCP with HD Extreme. It has a better refresh than other cards I’ve tried. If you want top of the line for color correcting/monitoring in AE on a PC, look into that Nvidia GPU card with the SDI output. I’m not a PC guy but the way I understand it is that card is for monitoring only. You’ll get the AE GPU speed boost and instant refresh but may need a second card for your editing/input/output. Someone correct me if I’m wrong because I’ve been keeping an ear out for a Mac version.
Chris