Many human models seem to be (slightly less than) 64 quants high, so we've been going with a rough 32q=1m. Another benefit of this is that I can go outside and scream "1 meter! Lucky 32! Lucky 32! Who wants one meter? Going once! Going twice! GO AHEAD AND CALL THE POLICE. SEE IF WE CARE!"

The police take quant bribes in powers of two, which 32 is one of.

I tend to find that whatever you go with, establishing an actual, concrete metric helps keep things in proportion.