Hi from a fellow Aussie (Southern Vic here
I've been hosting with DreamHost for a little while and overall the experience has been a pleasant one.
The time-zone difference isn't a major problem, I have almost trained myself to think in two time zones now. Since I have been with DreamHost I've had a couple of small outages, but support requests sent via the Web panel were answered promptly and the problems were resolved very quickly.
As for latency; Most of my visitors are not from Australia, so the US seemed as good a place as anywhere to host and the space/bandwidth on offer just wasn't available here in Australia, at least not at a reasonable price point.
I guess the latency might be an issue if most of your visitors are from Australia, but in my opinion this should not be a major problem. Pages might have a small initial delay before coming up, but in my experience this is hardly noticable and more than compensated for by the features offered by DreamHost.
Anyway, if you have any specific questions on hosting with DreamHost from an Australian perspective, ask away.
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