Just doing a ping using Speedtest.net test doesn't really show anything since they have multiple servers and you may connect to a server half-way across the country, while someone else may be connecting to a server hosted by their own ISP.
Speedtest.net also do their ping test before doing the actual speed test, so the ping is done while the connection isn't under load and doesn't reflect real usage of a connection.
Use the
DSLreports speed test to test the responsiveness on your connection. It runs a continuous ping both before and during the speed test so you can see what effect you downloading and uploading will have on your connection's
latency.
On the DSLreports speedtest results page ignore the raw ping values since it typically connects to a foreign server. Instead look at the
differences between the idle, downloading, and uploading ping values. The differences between my idle and downloading pings is only an additional 7ms, and between my idle and uploading 3ms. This nets me an "A+" grade for bufferbloat.