Comcast called us! "Have we got a deal for you!!!!!". They told the wife that our old modem was "out dated" and we need to "upgrade". I had 50 MBPS. She went down and picked the new modem/router and I set it up. PITA! I had static IP's and it didn't like those. Also I have a device that has a 192.168.... IP that I can't change and the comcast router uses 10.0.... so it doesn't work anymore. Spent hours! Ended up with over 80 MBPS but how fast do you really need. I didn't find out about the Xfinity WiFi signal I was broadcasting for months. I saw it but I figured it was a neighbor. They don't tell you about the Infinity WiFi signal and it comes shipped to you turned on by default. They trick you into being their hotspot. It's great for them and they don't really care about the customer since it's Comcast or nothing. The choice is yours.
The only advantage I got out of the deal was I used my old router as an range extender and now have WiFi out in the garage.