Attached Link: http://www.grisoft.com/us/us_dwnl_free.php

I appreciate the general 'caveat emptor' spirit but shouldn't it be reasonable to expect the seller to at least have some form of basic quality control?

If it's so easy to get an efficient virus (let's be sensible, I have one, a free one from grisoft (link above) and it worked so well as to be able to detect the virus that came with my marketplace purchase), if it's so easy then why doesn't the marketplace have one in place?

I shouldn't, for example have to laboratory test a burger before I eat one. Perhaps on second thoughts that's not such a good example.