Originally posted by Adam AFAIK if it's under the US warranty, they won't even ship outside of the US. You'd have to get a local warranty or have your lens services for a price
No that is not the case.
I'm in Singapore and there are plenty of Pentax users who buy online from the US. Local US warranty is a given but you can apply for international warranty from Pentax USA. So if you do have a problem with the item within the warranty period and you are not in the US, you can get service by the local Pentax agent. Do note that international warranty may be shorter in duration than local warranty.
Now not every country that sells Pentax gear offers international warranty. Buy your Pentax in China (PRC) and there is no international warranty coverage, only a local one, but the plus side is prices in China may be a lot cheaper than even in the US. So it is good to find out if the local Pentax agent does allow international warranty application/conversion. So if you buy Pentax, research on the warranty coverage provided. One thing to note is if you buy from China or Japan you will get local language operating manuals. Since you are in Australia, and if you're looking for Pentax gear, one option is to buy through Singapore. You can always ask the person to buy the gear for you, test on the spot and you can apply for warranty online with the option for warranty extension. Pentax prices are reasonable here and tourists get part of the GST refunded.
Here's a recent shot what's on the shelf of a local shop taken by one of our local Pentax users.
Now the example above relates to Pentax gear and assumes that the country that you are in does have a local agent that can offer warranty service. With other brands of equipment, you need to check. For example, where I am at, Sigma does not entertain warranty for lenses not purchased locally. That's because many Singaporeans are well traveled or net savvy and pick up good deals overseas or online, which means the local agent has to entertain plenty of requests for service (eg. the usual front/back focus issues).
Buying from the US is usually OK but with the return policy there, you can't really know if the item shipped is a returned item or not. Buying online and you buy blind, you can't test and you can't even choose your serial numbers.