[Al_The_Man]

But, would a 500 count @ quad 2000 be a good choice then to better my 10sec resolution target ?
edited in: or 2000 count encoder using simple step & direction hookup, is there even such a thing ?

I assumed you were using servo's, if using steppers then you probabally do not need encoders, as the resolution is decided by stepper.
BTW the correct term is 500 quad count x 4 = 2000. the term (quad)rature does not refer to the count in this context.
AFAIK Mach does not read encoder input. The feed back is to the drive.
I make it .002 per deg. for a (500/rev) 2000 counts encoder at 90:1 red.
Al.