In art, it depends on the look you are trying to achieve. Since IBL/HDRI is a new Toy in Bryce 6, we are of course, Experimenting and Playing with it. Where with our own experiments, and by following along with Agent Smith and others here, we are learning how best to use this new Toy, as it were.

Once the New Toy Factor wears off, then it becomes another tool to be applied when needed, for the desired effect.