It's going to composite everything into a buffer on the Mac just as quickly as normal. Transmitting that buffer across the Internet is going to run into lag. It

It's going to composite everything into a buffer on the Mac just as quickly as normal. Transmitting that buffer across the Internet is going to run into lag. It will be anything from a minor annoying delay to a completely unusable lag. You probably aren't going to do gaming or videos (or Quartz Composer, etc) on your remote Mac.