The MC16 has an uncoated piston crown, with rings of a different material, but dimensionally they're the almost identical to the MC28, so it is not only acceptable to fit the latest model pistons, but recommended. do replace as a pair though as their weight is different.
Also, the MC16 doesn't have oiling holes for the gudgeon pin, so all in all the MC28 piston is a better choice.
The MC28 piston is actually a good choice for any NSR from 16~28.