Maybe it's where you are located. I have VPN on all day without interruption when I work at home. My google ping was 32ms, yahoo was 35ms.
Comcast has 20mb/sec service now too.
(Sorry for the late response. I was on vacation
)
The issues I had weren't with ping times, but stability issues, like dropped packets. I was amazed at how bad the Comcast network was (tens of % in lost packets on some days). Beyond the lost connections, I would also experience severe speed drops during certain parts of the day to the point that websites loaded like I was on dial-up and my X-server sessions to work servers would be useless since each keystroke took a couple seconds to display and mouse events took several seconds to register.
It's possible that it was my neighborhood, but I know a lot of people in other areas had similar issues (as has been beaten to death on MyFolsom over the years *cough* mylo *cough*). It's also possible that they resolved their issues since I left three years ago. I'm sure the bad image they had was one of the reasons for the whole Xfinity rebranding. Maybe getting better IT folks was part of the rebranding!
As for the speed debate, it's mostly marketing hype to get people to pay more for something they don't need or even use. I have the 6 MB service and have no problems streaming Netflix or HD videos from other online sources. I think Comcast was at around 12 MB when I had them. I saw no significant difference related to the speed after switching to the slower U-verse service. I don't do online gaming, Skype, illegal video downloads, etc. Maybe faster matters in those cases?
"Just think of how stupid the average person is, and then realize half of them are even stupider!" -- George Carlin