I purchased a 128GB Lexar 633x card recently http://www.amazon.com/Lexar-High-Pe...p/B00O1M21H8/ref=cm_cr_pr_product_top?ie=UTF8 It is supposed to have write speeds on the order of 40MB/s, but under no circumstance am I getting much more than about 20MB/s - whether in transferring real files or in benchmarks, using the card reader or the usb3 port with the included adapter. Read speeds are good at 60-90MB/s and it's not counterfeit - I've nearly filled the thing and used it heavily for the last few weeks. Some other reviewers are reporting the same write speeds, while others are showing speeds of 30-40MB/s. Any thoughts? What write speeds are people getting from other cards?