Tech support said it was impossible to change the Gateway address (but I googled it and did it while on phone)

Neither the Xfinity nor the Arris tech support folks know this.

This is the only white device on my computer desk and it really sticks out (LOL).According to at least one of the tech support people I talked to, a lot of people don't actually upgrade to a VOIP compatible modem.

When the Internet connection was working the tech support agent then had to pass me to someone with the ability to set up the voice connection

Tech support was great

Tech support is very good

I didn't test this, but it is what I heard from Tech Support

Connected, but the phone part never worked thru Comcast after tech support.

Last 3rd party modem was difficult to get activated involving multiple calls to their tech support.

usb port is only for tech support only!!

Works pretty much as described out of the box (requires a bit of kickstarting from Comcast tech support, but whatever)

Their Tech Support did a good job walking me through the fix.

1 Gbps service requires a Docsis3.1 modem such as the Arris SB8200 (which may or may not work, I don't know).It took me 4 hours on the phone with 4 different tech support people plus two round trips to the local Comcast office plus an hour in person with the Comcast guy who came onsite to finally get the basic information listed above

after having spent hours on the phone with Comcast Tech Support over multiple calls I am giving up

But if you do buy this unit with the intention of using it for VOIP with Xfinity, PLEASE, PLEASE, PLEASE DO NOT CALL XFINITY TECH SUPPORT TO HELP WITH THE INITIAL SETUP OF THIS DEVICE!It comes with an excellent set of Quick Start instructions that can prevent you from doing what I did, which is spend over an hour frustrating Comcast Agents and Tech support people on the phone trying to get it all set up in one step.