For me, when I'm getting normal pings, my average ping time is around 50ms less than PTCL.
PS If they can give 20Mbps in 2500PKR then they can give 40Mbps in 4000PKR as well.
PPS I checked a PTCL DSL connection and you're right, I couldn't move out of the 39.x.x.x range which gives 250-300+ms pings to EU