When you are actually playing, you aren't actually using Ironclad servers - the game is P2P with the host syncing the game to ensure that everyone has run the simulation up to a certain point before the next round of simulation occurs. Lag is normally because one of the players cannot keep up due to data transmission issues or trying to run the game on a machine that cannot handle it (e.g. have graphics too high etc...)

I'm in Australia, so my ping to other people is often slightly higher then for US only people.

I've got the same problem, playing from Iceland and my ping to mainland Europe is 50ms and about 150 to North America and no problems with bandwidht either.