報告ないので風見鶏の一番安い>>510のmicroSDカード買って8割以上埋めてみて
古いPCで測定してみた、感想は値段なりでそんなに悪くもないかな
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CrystalDiskMark 8.0.1 x86 (C) 2007-2021 hiyohiyo
Crystal Dew World: https://crystalmark.info/
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* MB/s = 1,000,000 bytes/s [SATA/600 = 600,000,000 bytes/s]
* KB = 1000 bytes, KiB = 1024 bytes

[Read]
SEQ 1MiB (Q= 8, T= 1): 92.902 MB/s [ 88.6 IOPS] < 89528.24 us>
SEQ 1MiB (Q= 1, T= 1): 93.114 MB/s [ 88.8 IOPS] < 11241.94 us>
RND 4KiB (Q= 32, T= 1): 9.304 MB/s [ 2271.5 IOPS] < 14047.52 us>
RND 4KiB (Q= 1, T= 1): 8.179 MB/s [ 1996.8 IOPS] < 494.96 us>

[Write]
SEQ 1MiB (Q= 8, T= 1): 65.217 MB/s [ 62.2 IOPS] <121434.23 us>
SEQ 1MiB (Q= 1, T= 1): 21.390 MB/s [ 20.4 IOPS] < 48732.64 us>
RND 4KiB (Q= 32, T= 1): 2.014 MB/s [ 491.7 IOPS] < 64267.16 us>
RND 4KiB (Q= 1, T= 1): 4.319 MB/s [ 1054.4 IOPS] < 941.59 us>

Profile: Default
Test: 128 MiB (x5) [O: 83% (380/461GiB)]
Mode: [Admin]
Time: Measure 5 sec / Interval 5 sec
Date: 2023/01/17 21:15:21
OS: Windows 7 Home Premium SP1 [6.1 Build 7601] (x86)