Using it on roughly 4000 Macs running 10.7 and up. The only big issue we've had was with 10.8.x. There was a known problem where Wi-Fi would disconnect after 60 seconds and Apple made us wait till 10.9 for a fix.
We use 802.1x for Wifi and Ethernet, computer-based authentication (so the network is active before the user logs in). We use computer certificates for Wifi and the computer's Active Directory credentials for Ethernet. It works fairly well, minus some Apple bugginess.
Currently using SCEP/Network/Certificate config profiles to install root and machine certs for auth and auto-connect to Wifi. If you have a MS CA server, fire up SCEP and configure the default template. There's a couple blog posts out there that help out quite a bit. Make sure you include the entire cert chain in the Certificate config profile and trust them in the Network config profile.
I have been reading this thread with interest as I am also experience issues with 802.1X profiles. Is it possible for someone to post a screenshot of the particular settings you are using so I can compare against what I am doing and see if I can solve the problem? We had no problems with the profile I am using with 10.9.