How reliable is hdtune for testing hard drives?

I only ask because i bought a new Samsung HD502HJ the other day. And it will not load win7 i keep getting a corrupt file error please run chkdsk

So i have connected it to my main pc and tried to run a few tests with hdtune. First tried a read test and hdtune came up with a read error and aborted the test. Now i am trying a slow error scan and so far there are loads of red damaged blocks

So safe to assume this hard drive is faulty? I am only asking this because the company i bought it from are saying i will have to pay £15+ vat and a re-delivery fee if the drive is not faulty! Any other software i should use to test the drive?

Thanks

Try another SATA cable and port, otherwise it's busted.

Thanks for the reply, yep tried another sata port and still get the below result...

It looks pretty poorly. I'd run samsung's diagnostic, and it will almost certainly fail with fault codes. If you provide details of it failing Samsung's own test, it would be pretty hard for the supplier to then say it was OK...
I think this is the one: http://www.samsung.com/global/business/hdd/support/utilities/ES_Tool.html

Other options might be:
-return under the DSR if within time limit and buy another one
- returning to Rexo (who IIRC do Samsung's returns in the uk) for exchange - if they would accept it they are pretty quick but you might get a refurbished drive back

thanks i will try samsung's diagnostic
cheers