Not all of the approved modems are available for retail sale. The ones that are will have Retail next to the model number.
If you have any questions about any of them or want opinions ask in the Basic Internet Connectivity And Modem Help forum.
Comcast employees must be authorized to post in the forum in an official capacity. Employees posting here have their names in red and are designated as employees. Names not in red are customers.
This is done to protect customers and for assurance that they are dealing with a Comcast employee. Non-Authorized Employees are allowed to post but cannot state they are employees nor can they allude to being employees.