Quote - That being said, its not that bad. You will find that different HDRI's will render a scene faster than others (I'm assuming this has to do with the complexity of the actual HDRI image, and how many exposure layers were used to create said HDRI image.

Yeah, there are apparently two factors in that. One is the sheer resolution of the HDR image, while the other is the amount of detail in it. But simplified, the bigger HDR file is, longer it will render. And yes, upping the quality to the max will lead to mammoth renders. Not that we don't know how that looks like. :)

-- erlik