I was looking for a more 'bullet proof' option as an alternative to the HY chinese vfds. Seems that the wj200 is a pretty common suggestion. At 340$ its pretty pricey at a hobby level.

I was looking at a few other options and came across this: L510-203-H1-U - about 230$ based on my shopping
single phase input at 230v
the brochure: https://www.tecowestinghouse.com/PDF/L510_brochure.pdf
says the frequency range is 0-599hz. Most chinese spindles are 400hz.

Does anybody see anything that would suggest it wouldn't work well for a mach3 controlled setup?