Slow Render In FCP

Hi,

I've been importing motion project files into FCP. The render is ridiculously slow from within FCP. I can output the same composition as a QT file directly out of motion in a fraction of the time but then I lose the ability to have changes updated in the FCP timeline. Anyone know why there would be such a big disparity in render time?

I'm using a 2.7 dual with 8 gigs of ram.

Thanks,

Hal