SanDisk 128GB Extreme SDXC UHS-I Memory Card - 150MB/s, C10, U3, V30, 4K UHD, SD Card - SDSDXV5-128G-GNCIN

I tested this drive with a USB adapter for a PC, and tested with large video files to get an idea of the read/write speeds.The read and write speeds exceeded the specs, working with about 15GB of data. I was reading at about 185 MB/s over 15GB of data read from this drive and written to an NVMe which is a bit faster. Considering this is rated for 150MB/s, that's VERY good.The write speed was also excellent. This disk is rated for about 70MB/s and I got closer to 85MB/s. Once again, writing to this drive, and coming from an NVMe, it was writing at about 85MB/s, and this is rated for 90MB/s.However, the way my system wrote to this drive was almost as if this has about 4GB very fast cache, or it has a small segment of very fast storage, because my system showed that within about 5-6 seconds it had already written about 4GB to it. Then it slowed down and it was showing something like 160 - 180MB/s for a time period, and then the write operation for the PC showed as complete. The USB adapter though was still showing activity, meaning that data was still in the process of getting written, and probably from it's fastest storage to slower storage. The time I calculated for the write time included all the time that the USB adapter was showing activity. If I would have based the write time on when the computer showed the write was completed, the write speed would have been more like 100MB/sI tried to read about these SD cards but couldn't see anything about faster cache or a small amount of fast storage, but that's the way the disk seems to work as far as what the Operating System showed. I know that modern SSDs use that strategy to improve performance, so when you test write operations, you always have to write more data than the size of the cache to see the speed that the main storage runs at.Also, the read/write speeds are listed as "up to", so there is no guarantee that you'll get the speeds that are listed for any period of time. All I know is that working with 15GB of data, this disk performed exceptionally well.Either way, I'm very impressed with it, and as long as it lasts a long time I'll be happy. It was a great price when I bought it and worth every penny.

The SanDisk 128GB Extreme SDXC UHS-I Memory Card delivers impressive speed with up to 150MB/s write performance, perfect for capturing high-quality photos and 4K videos. I don't use any other brand and trust their reliable brand because it ensures durability, quick writes and dependable storage for all your photos.

This card was used to store the operating system for an industrial machine.Any time the machine needs maintenance, adjustment, to have a jam cleared, or other type of human intervention, power to the machine must be shut off. After the maintenance has been performed, the machine then takes a few minutes to load the OS and start back up.With over 70 machines on site, delays in starting machines can start to add up. The faster the machine can boot up, the sooner it can return to service. I've had excellent success with USB flash drives from SanDisk for both speed and longevity, so this SD card seemed like a winner.It appears to operate as advertised, and after a couple years 24/7 use, it is still working just fine.

Exactly what I needed. Great price and good reliability.

It gets the job done and that is all that's needed. I would recommend and also purchase again. Thank you for a good product. My camera and I love it.

Although pricey, this Super fast card is worth it. Loads of memory storage, works perfectly for digital still shot and video cameras, especially for above 1080p to 4k Ultra resolutions.One thing, you must make sure that your device is compatible, this card will either not work or will improperly function if your device cannot handle it's speed and memory. Check your camera specifications first.Also, good idea to transfer and back up these files asap to an external hard drive, because having so much storage on one card could cause a glitch that may cause you to have to format the entire card because of one corrupt file.For the most part, this is a great card, pricey, but worth it. Works perfectly with my 4k Ultra Sony Cam.

Works great and it matches the ones 3x the price

10/10