I have a Toshiba 320 GB Hard Drive. I have it on a USB device to test it right now. Chkdsk says no bad sectors but SeaTools from Seagate says Failed with the short test and the long test. So is this drive good or bad?

I have Data Lifeguard and did a low level write zeros to the drive and then ran Seatools and now it shows Not Failed on the tests. So now is the drive good or bad?

Is Seatools or any other hard drive utility a better test than chkdsk to know the integrity of a drive?