Where I live, Telstra are literally a joke. They made us use a congested 3G tower with 9mbs backhaul for 5 years. Then Optus came along and gave us 14.4mbs 3G at half the price, and then 2 years later 70mbs 4G. A year after Optus, Telstra upgraded their service to 14.4mbs 4G, shared with the 3G.
The Telstra tower was often down for 2 weeks at a time, whereas Optus never failed.