Attached is a better render sample using one of the HDR images from HDR Capsule:Studio Lights.
You can see the very soft shadows created from the Adaptive Skymap as well as a combination of RT Reflection Skymap, and GI Glossy effects.
All of the HDRs are meant to give good results right away at the default settings, so you don’t have to wrestle with the controls to get results. But some simple tweaks can be useful.
Because these images were “engineered” rather than photographed, they have some special properties. For all of the images in the Studio Lights series, the saturation from the light sources is controllable using the clamping control within Animator. You can see in the sample that pulling the clamping down to about 30% of the max pulls most of the color out of the light sources, but leaves the soft shadows intact.
As for speed, these images used 400 Primary rays, and rendered on my “old” 2ghz G5 in 6:30s. Not too shabby 
I hope everyone will find these useful!
I’ll be sharing some more things soon!
As always, feedback is welcome 
Dave