Just bought for €25+shipping this sdxc card - Sandisk extreme pro, because I was curious about the claimed speed of (up to) 170MB/s

I've tested with Danne's build crop_rec_4k_mlv_snd_isogain_1x3_presets_2019Apr09.EOSM202
and achieved speeds around 56 MB/s in the 2.5k preset.
In the cardreader Transcend TS-RDF8K I've run the blackmagic diskspeed test which were 75MB/s Write And 79MB/s Read, and used also the F3X soft to test the Card, which test it passed, however the sustained writespeed was around 72 MB/sec.
Even this card doesn't perform as advertised, I think I will keep it.