There is also f3, which stands for fight flash fraud. A longstanding program for checking out purchased media. It is multiplatform, however it is distributed only as source, however some distros do include it (Debian has it).
I just bought a 1 Tb. 2.5" Crucial BX500 from Amazon, from the Crucial storefront there, for around 50.00. To me it seems to be an amazingly good deal. Maybe just buy from a reputable vendor/manufacturer and don't look for stuff that's too good to be true?