some guy "some guy in ny"
I ordered these cards at a great price during black friday week/weekend.  I began loading some files (music, videos, pics, etc).  The first card worked without any problems.  The second card started giving me cyclic redundancy errors.  At first, I thought it was my hard drive that was failing, and tried to copy the same files to a flash drive which worked just fine.  Ok, maybe I received a dud, and tried with another card from my purchase.  Same results, cyclic redundancy error.  I started searching online, and found a utility via one of the reviews on Amazon called H2testw.  Ran the test on both cards, and it reported errors.  It also reported write speed of only 4MB/sec, which is way below advertised speeds.  These items were in retail packaging, and I remember reading about the bulk package items being fakes.  I guess the retail package cards aren't any better.I should have waited to do the refund because now I have to process the refund seperately.  I will test another card to see if I have better luck.  I wanted to leave a 1 star, but I gave 2 stars since 1 card worked so far.  I have 2 more to test.Very dissapointed because I was a fan of the Sandisk Ultra series for being reliable, but I guess they are cheaping out on quality to increase their profit.  I would have been extremely upset if I used these cards for anything important.