This 256GB microSD card has 235GB of usable storage space when formatted in exFAT. On average, the sequential read-write speed after several runs of CrystalDiskMark was 95/75 MB/s and the random access time was around 7/2.5 MB/s. This is in line with the advertised U3/V30 specs, so it's good enough for DSLR and video recording. I can also confirm that it works on my Nintendo Switch after reformatting. Screenshots of benchmarking and performance tests are included.
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