[JohnR]

I need to buy a few good SD cards and looked on eBay. Nice cards from eg Samsung at good prices. Then I thought hm, sellers with names like "ozbargainseller" don't really sound like a computer parts vendor...

Apparently a lot of these are fakes -

http://www.ebay.com.au/gds/Spotting-Counterfeit-fake-SD-Micro-SD-USB-Memory-Cards-/10000000175807852/g.html

FYI 

[FullRangeMan]

I suspect Iam using fake DVD-R I buy in local shops as they show only 3.3Gb in my PC, the brands are Elgin and Tech-LV 

[timind]

Not just ebay sellers. I bought a 512gb SD card from B&H Photo which turned out to be a fake. I was glad I bought form a reputable site as the return/refund process was painless. Ended up getting a PNY 512gb card from Amazon which is working fine in my ipod.

[Wind Chaser]

I have Samsung SD card I bought online about two years ago... it’s still in the package. At the time when I bought it, it seemed like a pretty good deal, although I don’t recall how much I paid or where I bought it from. Which reminds me I bought a new Netgear router last November; I need to unbox that as well... 

[randytsuch]

I've bought some fake usb and sd/cf cards over the years.

These days, I buy from my local frys, or amazon.

[Wind Chaser]

So I opened the Samsung card I have, SDHC UHS-1 32 GB. I copied 26.8 GB worth of files from my computer in just over 24 minutes at an average speed of 19MB/sec with 2.93 GB space remaining. Capacity and speed wise  that seems about right.

[JohnR]

Not just ebay sellers. I bought a 512gb SD card from B&H Photo which turned out to be a fake.

Yikes!

I'm thinking it's probably a good precaution to run a speed test on new SD cards....

BTW my tip on a fast card at a decent price, Toshiba Exceria Pro M401 (or N401). Most cards when they proclaim e.g. "90MB/s", that is only the read speed, the write speed is half or less. That particular Toshiba has fast writes as well - I measured 84 MB/s read and 72 MB/sec write. (With a speed test program, not file system copy which may be lower.)

NB has to be that model, not just any "Exceria" card, there is a range with differrent specs. There's a really fast one too but not a nice price.

http://www.toshiba-memory.com/cms/en/products/microsd-cards/exceria/index.html
http://www.toshiba-memory.com/cms/en/products/sd-cards/exceria/