I don't use MB color effects so can't compare there. From recent threads I saw, MB does take a while to render, so that will definitely increase export times beyond the norm. Also, source format and export format make a difference as well, so we're comparing apples and oranges unless everything is relatively matched up between us.
My source files are usually 1080i HDV, and exporting to MPEG-2 DVD or H.264 for web. DVD is faster than realtime, and H.264 for web can also be, though Blu-ray may take a little longer than realtime. But never anything like you are seeing.Third-party effects are the wild card with rendering times.
Jeff