I have actually been pleased with the results I have experienced so far using converted custom DAZ avatars with my motion captured files. I think all of my characters are DAZ avatars, so I can't say for sure that the Iclone figures might not show some slight improvement, but I doubt it.
There have been some issues, but I think they are related to me learning how to best use the hardware, and not related to the avatars.
I'll try to post some samples here in a day or so.