wondering how i go about getting the updated wifi unit and is there any difference in a monthly cost.
All Comcast Gateways have the same rental fee.
I have successfully replaced many Comcast gateways since I became a customer in 1982.
I replaced my XB3 with the XB6 last year.
Try calling 1800comcast - ask for Inteernet support. I am paying for the service contract and a tech installed mine.