Review on ARRIS Surfboard SBG6700AC (8x4) Docsis 3.0 Cable Modem AC1600 Dual Band Wi-Fi Router 📶 - White, Certified for Comcast Xfinity, Spectrum, Cox & More - Max Download Speed: 343 Mbps by Alex Winnick

I bought this unit (white, SURFboard AC1600) when I switched from CenturyLink to Xfinity. As others have said, it worked great for a month or two and then I noticed a decrease in the quality of service. First I called Comcast to find out why my speed was 25% of what I paid for. They kept telling me they didn't see any problems and it must have been my gear. This is where you need to understand how ISPs work. They regulate traffic based on what they consider acceptable 'usage'. I also have a feeling, although not proven, that they can use the same traffic throttling to get your hardware working. This will eventually get you trying out their hardware (at $10 or more a month) and I'm sure you'll suddenly get back to your fast speeds. That's just my theory. Anyway, after a month of very slow speeds, I've come to the conclusion that I can buy a new router/modem, try ISP gear, or get a VPN. The cheapest of these three options was a VPN. $7 for a month, worth a try. After installing and configuring the VPN (only about 5 minutes) I was back to ultra-fast speeds. Just wanted to mention this for those of you troubleshooting slow performance issues, especially with Comcast/Xfinity.