Started testing a week or so ago, and my first reaction is that I miss the increased power of the VRayHDRI loader -- a Corona version would be fantastic. The Max bitmap loader is a pain to work with for HDRI.
I would just continue to use the Vray one, but I'm getting an additional computer and don't want to repurchase VRay if I don't need to.
Small thing, but would be nice :)