I think that the ping time is not all that relevant. The more important number to keep an eye on is the overall throughput, measured in Mbps (mega bits per second). Speedtest gives you that measure.
With the DSL, the highest is around 5 Mbps. Sufficient in most cases. Cable can go from 10 to 20 Mbps. Fiber is even higher. Most hotels I stayed at, via wifi, can only do 0.5 Mbps to 1 Mbps. Bad if you have a lot of charts.