Buying stuff in New York

Cameras seem quite a lot cheaper in New York, judging by the website of photographic suppliers B&H.  However if you walk into their shop and buy you need to add the local sales tax, of about 9%.  Also if the camera value exceeds your "personal allowance" limit of $NZ700.00 then when you re-enter Aotearoa you will pay 15% GST plus about $30.00 in customs and MAF fees for the privilege.  So, according to my little spreadsheet on the subject we would save about 30% if buying a Canon S95 in NY (less than $NZ700 worth) but save little or nothing if buying a Canon 600D or 60D, say.  I'm actually interested in the Panasonic G3, which is not available here yet.