Any advantage to regulating contrast w/ opsz vs ctst?

Glyphs
1

I’m designing an 18-style typeface with six weights, each with three different degrees of contrast. The different degrees of contrast do not map to optical size. Should I use the opsz axis to govern contrast anyway, since it’s more commonly used than the ctst or contrast custom axis? (I’m not sure yet whether I’ll publish this as a variable font; the main usage will be static OTFs, but I’d like to reserve the ability to publish as a VF as well.)

Thanks!

2

As I understand it, some applications will set/change opsz axis setting with point size, so if that is NOT what you’d want you may want to steer clear of opsz.