Replacing Comcast XB6 Modem

I would appreciate advice on replacing my rented comcast xb6 router/voice/modem with equipment that I own.  I have not been able to find docsis 3.1 gigabit equipment. I think it is best to use separate internet and voice modems and a router and I've looked at the cm1100 but netgear says it is not compatible with cable bundled services. does this mean it wont work if i use a separate voice modem? If so, what do you recommend. thanks