just a question, because someone mentioned this and it seemed really crazy to me.  are you guys using IDL with IBL?  because that seems like a really bad idea.  the whole reason to use IBL is to fake what IDL does.  i can definitely imagine problems putting the two together.  maybe bagginsbill will set me straight, but if you're having artifacts when using the two together, that could certainly explain to me why so many people would be posting perfect, artifact-free renders while you guys aren't able to get past them.

personally, i'm planning to hold out for Pro, so i don't have my own direct experience to test.  but i know i'll have to change my lighting to use only directed light and ambient colors in my future setups.