If I see a HDD or SSD with bad sectors I throw it out or seek refund/replacement.
Yes, I had a brand new SanDisk Ultra II with bad sectors, SanDisk replaced the drive and all is well.
The bottom line is the drive would not format under Windows 7 (untick the quick format box to format and erase).
Quick Format will often create a new file table and give you the false impression that the disk is OK.
Format creates a new file table on a disk and fully erases any existing data on the disk.
It is when trying to erase the disk that errors will show up and the disk will not format.
Another way is to go to the command line and when trying to erase the entire disk it may report an error, in my case it reported a semaphore error.
Also check the Win7 system log in the Control Panel for Disk errors.
Bottom line, if you cannot Format and erase the drive, it is unusable.
