Haven't gotten around to use the lvoely birds, and I admit i havve a bit of a trouble making them look good in Iray, likely because I haven't gotten used to iray properly yet and not really know how to handle it...
The bird materials weren't tuned for iRay (which was still in the development phase when the product was released)... so that's probably part of the issue... You'll see much better results using 3D Delight. As part of my huge upgrade process I'll be working through the rest of the year, I will be adding iRay and Poser Superfly materials to all the sets (but that's over a 1,000 birds-- so it's going to take a while).