Comcast DNS Server Issues

This is more of an observation than a question. I have been having connectivity issues with my internet over the past several months. It is only occasional but after some debugging with Wireshark, I found that the Comcast DNS servers had significant response delay (>3 secs) when these issues surfaced. When I switch the modem to use Google's Public DNS servers, the issues went away (<<100 ms delay).

Anyone else experience something similar?