On the statement, "a pro may only use professional products, to appreciate his work!" - I've always doubted. As for cameras and lenses may approve it, that you get what you pay for. However, whether the interior of a memory card is entirely different if the product name and the purchase price promise quality, may well only the dealer or producer advocate. My Komputerbay 64GB Professional CompactFlash cards with the fastest read and write speed, have certainly never shown weakness despite the toughest conditions on my safaris and adventure travel. Even a hand wash in your pocket, where the card has been forgotten, had survived this product harmless. She is still in use. So what should induce me to pay at least three times for this product, just because SanDisk or Lexar draufsteht. Technically, all memory sequences, regardless of who created them, exhausted after 500 overrides. It is better therefore to keep track of how often one uses a memory card instead of paying attention to the product name. The quality of an image in any case originated in the mind of the photographer and not in its equipment.