Well I tried to get my MicroSD 64GB Samsung EVO Plus working in 2box. Even with my IT expertise I wasn't able to crack the formatting problem after a couple of hours, stopping short of making a Linux bootdisk. So I cloned the original using MiniTool as recommended. Easy, extended to 64GB, works, but inefficient.
Surprisingly while I was testing, one of the default snares on the original MicroSD cracked up really badly. Alarming that my MKII had an audio anomaly that early - I hope it isn't a problem.
The original 2box MicroSD beats the Samsung by about 0.4ms less on average read access - so I am still looking to procure a better 64GB card.
Best bet I found is an
WD IX QD334 Industrial microSD 64GB SLC however it has proactive error checking so it could cost some latency. Difficult to discern details at this technical level without sending a few emails.
Worth a punt at £92?

It's not that bad considering the higher seq write speed SLCs go for £500+
Most other manufacturers I've researched cap their SLC line ups at 32GB unfortunately.