Non of what you mentioned is wrong, but i was mainly talking about the general pool address, try pinging it from a different location and you will see that you are getting a reply from a different IP address, assuming you have the same speed from the different locations you ping from, the result will be very close.

It is however advisable to use the one closest to your location, but overall, if you do ping the pool and get terrible results it means you should find another pool.

OP can try the urls you provided and use the one nearest to him, chances are he will still face the same problem.