That would depend on what packages are available in your area. I use an Arris SB8200. I am on the 200Mbps blast package. The SB8200 supports DOCSIS 3.1, which may not be avaialble in your area yet, but it would be wise to consider buying a modem that supports DOCSIS 3.1. The 8200 is capable of speeds up to 1.2 Gbps download speeds. It is a future proof investment. When DOCSIS 3.1 is available in my area, or faster speeds become avaialable, I am ready for them with this modem.
Please see this page for useful links and information:
https://www.xfinity.com/support/articles/list-of-approved-cable-modems
