Sony 64GB microSDXC Class 10 UHS-1 Memory Card

CUSTOMER REVIEW



Over the past decade I have purchased dozens of memory cards. My two favorite brands are Sandisk and Transcend since they always give consistent (though maybe unexceptional) performances. Recently I bought this Sony 32GB Class 10 Micro SDHC R40 Memory Card (SR32UYA/TQMN) during a Gold Box deal, and it turns out to be my best microSDHC card.



I tested this Sony card using several benchmark programs, including CrystalDiskMark v3.01, Flash Memory Toolkit v2.0, and H2testw v1.4. See the pictures I uploaded to 'Customer Images' section for benchmark details. Here is a summary of my results:



- The Sony UHS-1 card delivered an amazing Sequential Write speed of 20.75MB/s. In comparison, the SanDisk Ultra UHS-1 microSDHC Card SDSDQUA-032G-U46A only delivered 12.6MB/s in the same test. So although both cards are marketed as 'class-10', the Sony card is 65% faster than the Sandisk one.



- The sequential Read speed was measured at 35MB/s, which is actually limited by the USB2.0 port I used. With a USB3.0 port I expect it to read much faster. (The card is advertised as '40MB/s') <-- [See update below]



- The Random Write speed of smaller files (1MB-15MB each) is equally impressive at around 20MB/s. In contrast, most other cards give much slower Random Write speed than Sequential Write speed. Random Write speed is especially important when the card is used in a digital camera, for example.



The Sony UHS1 card is faster than all my other microSDHC cards except for the Lexar microSDHC 300x UHS-I Card LSDMI32GBBNL300R. The two are actually neck-and-neck in performance, but the Lexar costs over twice as much. Currently both Sony and Sandisk UHS1 microSDHC cards are available at nearly identical prices, so the Sony card is definitely the best value.



[Side Notes]

- The capacity of this '32GB' card, as reported by my computer, is just 29.5GB. This is actually normal because computer people count one 'Gig' as "2 to the power 30", which is 7.3% larger than one billion. So 29.5GB come to about 31.7 billion bytes, which is rounded up to '32GB' by marketing people.

- The card comes formated in 'FAT32'. If you want to store video file greater than 4GB, you need to reformat it to 'exFET'.

- The actual microSDHC card is made in Taiwan, but on the SD-adapter it says "Made in China" which may be confusing.

- On the package there is an offer to download a free "Memory Card File Rescue" program from Sony web site. I don't see it as very useful since it allegedly does not work with non-Sony memory cards.



[Update on Dec 26, 2013]

I re-tested this Sony microSDHC card on an USB 3.0 port. The sequential Read speed jumped from 34.8MB/s to 47.3MB/s, which is better than the advertised '40MB/s'. The Sequential Write speed remains virtually uncharged at 20.6MB/s.