128GB and up could consume too much power from the Pi5, especially fast cards, resulting in unreliable operation. YMMV. Cards this large will work better if connected directly to the Pi5 and not using the extension.
A SanDisk 64GB Max Endurance or Extreme Pro will work fine anyway. I’d prefer the Max Endurance, because of endurance, because there are many writes happening during use of the Zynthian. The high speed features of the other do give a tiny bit of an advantage, but not enough to outweigh the benefit of greater reliability.
NVMe is the best in all aspects.