Sandisk Extreme Pro - Flash Memory Card - 64 GB - SDXC UHS-II (SDSDXPB-064G-A46)

Unfortunately the three cards (two 280MBps and one 300) I purchased last year from Amazon proved to be counterfeits, with tested speeds 44/24 Mbps. I tested other older slower cards on the same adapter and measured 88-90 Mbps, exactly as stated on the cover. The fake ones say "Made in Japan" and "Made in Taiwan" on the back. Performance on video even with a small camera is abysmal. I kept the cards and will probably send them to the authorities. I should have tested them earlier, though I just had them as backups.

Purchased two of the Extreme Pro 64gb cards, and have tested using two, brand-new Kingston USB 3.0 Media Readers, both of which are fully UHS-2 supported. Maximum Read Speed using SpeedOut v0.5 was 200-206 mbps, and maximum Write Speed was 145 mbps, about half of the advertised speed of "up to" 280 mbps. This may be why these particular cards are "Currently Unavailable" on Amazon? Should I complain? I did get them for half the price that hey are selling for in other outlets.. $200 each! But consider that I just bought two more of the 128gb Extreme Pro 95mbps, for $64 ea., that test out at a consistent 87-88mbps; which is more than fast enough to use in my GH5 for 4k, 100mbps recording. And twice the capacity!

WOW SPEED. What a difference.Was using a 95MB write speed/128GB card from SanDisk (PRO). A great card but when married to my Canon 5D Mark lll, it was slower than I would like or hoped for.Best Buy had this 64GB /280MB write speed card for $200. Amazon had it for HALF PRICE / SAME CARD. Amazon got it to the house the same day. Amazing price and shipping speed.In the continuous burst mode, shutter down; it can process the shots with ease and with very little shutter/processing lag.Great product. Worth every dollar.

Fast reliable SD card that is a benefit for the new cameras to store and transfer files to and keep the buffers open longer. They allow more shots much faster for longer.

Bought 2 of these for my pro DSLR that requires the high-speed transfer of data in order to quickly save both jpegs and raw images. Since these SD cards can only be judged, ultimately, by how long they continue to function, my rating is strictly based on their speed.

Got it 20 months ago for a trip to China. Excellent. Very fast got great pictures.Still using it!

Very good memory card. Fast to read/write. Comes at a very high cost, but I bit the bullet.

Not Lexar for sure....over the last few months, I have had 3 cards fail! Of course, now that Lexar has been sold, not sure which cards to trust with valuable once in a lifetime photo ops.