Managed to get my hands on a LightsphereII Photojournalist. Did a quick snap of popeye with the various diffusion methods. This is by no means an exhaustive test. Posting this anyway to share. Hope you can gain something from this!
All shots f5.6, 1/30s, 54mm and ISO400 using Canon 550EX. Halogen lighting in the bg to the right.
PS: Apologise if the image is too large for your screen