BlitRect
BlitRect(sourceImage, sourcePoly, destImage, destPoly)
Additional Notes
The FCP manual states that BlitRect is "treated as opaque," but that's a little misleading. What BlitRect actually does is completely replace pixels in the destination buffer. If the source pixels are transparent, the destination pixels will be transparent as well. Considering how much slower Blit is, in most cases BlitRect is a better option
Using a simple speed test filter to compare Blit to BlitRect, Blit took 30% longer to render.

