Summary: Great product, not much to set it up other than speaking with the right person at comcast. However, I am using a Cisco WRVS4400N Wireless-N Gigabit Security Router - VPN V2.0 In order to use Docsys 3.0 provided by my new modem, I had disable IPS security, otherwise the speed will not go beyond 4 GBps, it took me a while to figure out, nobody at Comcast would have a clue. I was advised by Cisco tech support.
Summary: Works great with Comcast in my area. I have had it running for about 2 months now and have not had to reboot but one time. Since it was on the "approved list", I did not have to touch the config, the Comcast installer did it. He had a few problems, but was able to work through it and get it configured.