Is a Motorola MT8733 WiFi 6 Router + Multi-Gig Cable Modem with DOCSIS 3.1 compatible with an Xfinity Xi6 wireless box? I spoke to TWO DIFFERENT Xfinity representatives over the phone today. One assured me that it was, informing me that, contrary to what I may have read or heard, it isn't necessary to rent a modem from Xfinity to have an Xi6 box shipped to me. Another representative I just spoke to told me that the person I spoke to earlier today had "bad information" and that indeed I need to rent a compatible modem from Xfinity. So what is it then?