I believe (I could be wrong), that what really matters is horizontal sync, which arcadevga locks at 15.75, to make a real monitor work without losing sync every time the resolution changes..
From experience I can say that my new happ vision pro monitor doesnt lose sync when swapping different (real) jamma boards, ie, I used the test modes on my Contra to set it up, popped in a Cobra Command, Bad Dudes, and then finally my Neo Geo..