There are numerous posts on eBay and the Internet outlining how to 'spot' a fake.

The simplest way is to look at the price.

If the product price is well below retail, then it's likely the product is fake.

So what you say!!!

I tend to agree that if they look the same, have the same capacities and perform the same functions, then at the reduced price, why not.

But consider this:
Capacities can be lower than that stated on the drive.
Read and Write speeds will be slower which when you are copying Gigabytes of data can be time consuming.
Reliability is reduced with the lifespan of some fakes considerably reduced.
Risk of losing data.
No Warranty.
Difficult to communicate with sellers for refunds if they are from overseas.

Use a local reputable dealer with a high feedback score who will cover their products under warranty.

Kingston USB keys for example carry a 5 year warranty.

Good Luck and PLEASE, mark this guide as useful