Dingoblue rocks - but it's closing down. ihug is shit as is froggy as far as connects are concerned and Optus and Telstra are a rip off for what they offer.
The best I've seen for under 30bucks a month is iprimus
www.iprimus.com.au as it has unlimited time and downloads (with a cut off after 4 hours its only drawback). Most people I've spoken to have zero issues with it so I guess that's where I'm going to move to.