purism@gnu-os:$ sudo hdparm -tT /dev/mmcblk0
/dev/mmcblk0:
Timing cached reads: 1764 MB in 2.00 seconds = 882.26 MB/sec
Timing buffered disk reads: 500 MB in 3.00 seconds = 166.54 MB/sec
root@gnu-os:/sys/kernel/debug# cat mmc*/ios
clock: 200000000 Hz
vdd: 21 (3.3 ~ 3.4 V)
bus mode: 2 (push-pull)
chip select: 0 (don’t care)
power mode: 2 (on)
bus width: 3 (8 bits)
timing spec: 10 (mmc HS400)
signal voltage: 1 (1.80 V)
driver type: 0 (driver type B)
clock: 50000000 Hz
actual clock: 50000000 Hz
vdd: 21 (3.3 ~ 3.4 V)
bus mode: 2 (push-pull)
chip select: 0 (don’t care)
power mode: 2 (on)
bus width: 2 (4 bits)
timing spec: 6 (sd uhs SDR104)
signal voltage: 1 (1.80 V)
driver type: 0 (driver type B)
Looks really nice overall, so yes i strong recommend a SDR104 SDCard for Librem 5 even over the bottleneck-usb2.0.
Also this confirm that L5 is huge better that PPP o PP.