If your ping is truly "fine and consistent", then you wouldn't be experiencing network lag.

Pings are one of the first things that get sent to lower priority in the traffic shaping policies when congestion is detected in route. The TCP protocol can also throw it's own mechanism in as well when it detects high error rates/congestion.

So, if your route is clean as you say, then you should not be experiencing the lags, just like so many others do not when their routes are clean.

Oh, and this game is NOT hosted in the USA, so that is not a fair comparison.