I tried these, and I didn't like them at all. They were very dry (when dh went to try one I said "get a glass of water first") and I ended up throwing most of them away.... and I LOVE doughnuts.
I'd be interested to hear if anyone else enjoyed them though.
I did find another doughnut recipe that turned out quite well... here's the link:
http://forum.lowcarber.org/showthread.php?t=163651

Jenn