3 days is not long enough imo ,wait to hear from him first
and keep an eye on his ebay actions in the meantime .

spoiling your 100% feedback works both ways ,so i guess
its a matter of how good his feedaback is ,cause he wont want that
ruined either if its solid .
on the other hand getting 1 neg feedback wont kill you
i have over 300 positive feedbacks on ebay and only 1 neg from
a seller that is noit registered on ebay anymore
i dont loose sleep over it though .