I'm actually rendering a pic right now where I'm "faking" the AO. I'm still using an IBL diffuse light, but have resorted to Occlusion Master for the AO. Yes, it's still Ambient Occlusion, but it renders MUCH faster than AO on the light would do. Don't know why, perhaps face_off can explain it? The past week I've been making a series of pictures with full AO and IBL, and allthough they're very pretty and look "real" they each take about 6 hours to render and I'm really not that patient L (and unfortunately, due to the content of those pics I can't show them here)

FREEBIES! | My Gallery | My Store | My FB | Tumblr |
You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.