AV/FW Software from different ebay sites

Hi folks,

I was reading on the net that buying software from places
like ebay india can result in great savings.

For example a popular av/fw all in one solution might cost 80 dollars on the .com
but if you buy it from a less expensive country/domain, you can save a packet.

Is this true? or a illegal software?
One guy was saying it's true, and he contacted the relevant company and asked them to check if his 'code' was legal, they said it was.

Cheers