Re: ADSL2 user here (wave)
Don't stress. Here in Tassie, I've been to places that are connected via NBN wireless and telstra where they don't get ADSL speeds unless its about midday during the week.
Haven't hunted down the information as yet, about contention issues and various providers. Mind you if the kids wail one more time about ping time. I might just be tempted to upgrade to a shitty service( for the giggles although I do know that our tower is okish 5-12Mbps with the odd laggy spot of 2-3 every few minutes. Only 1 hop away from a well connected exchange )
A little bit of knowledge can be misapplied so well.