Have had 2 of these, both have failed within a month.
First was from Scan. That was clicking and then died at the BIOS stage. Before this bad sectors started to show up.
Second was from Ebuyer. This has stopped loading data correctly and had exactly the same issue - bad sectors.
The SMART data (viewed through the SMART Tool in Parted Magic) showed that SMART was also logging these issues.
Now I'm very careful with disks. They have their own enclosure and are never moved once installed. Because of the issue with the first drive I did the long self-test with Samsungs own testing tool (ESTOOL) before putting any data on it. It passed fine with no issues, which suggests the bad sectors are happening after.
HDTune / HDTach was showing huge spikes once the issues started to happen, and this mirrored the OS performance I was experiencing.
Really not happy about it. I had always found Sammys to be very good before this.