I went with the 1TB model of the ADATA XPG SX8200 Pro. But that might have been a mistake as it does not work that well with my MNT reform 
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It is detected, but it is really slow compared to the SD-card. E.g. I can read every line systemd prints out when booting from the NVMe. When using the SD-card all that just flies by.
Gnome disks reports 90.6 MB/s read, 33.6MB/s write, average access time 104.06msec.