What is OK stale shares %? I see 0 stales on my Antminer sw and 3.14% Litecoinpool.org.
3% is pretty bad. Most users are currently below 0.25%. Keep in mind that stale shares are caused by latency. And unfortunately latency can be introduced by many different things, from overclocking to networking hardware getting in the way.
I mentioned this a few months ago (post #1398). Mine are also ranging from 1.68% to 1.75%. They seem to have peeked out there. They steadily rose this year. Before they were all at ~.35%.