I think one or two drops is as good as it gets. Other types of faucets can leak a small stream after being closed. My 630ss's also drip once or twice after pouring, but I'm fine with it, that's what the drip tray is for. Could just leave the glass under it for a minute if it bothers you.
I have 630s also but in chrome. They also drip a few drops after I close them. I think it's beer left in the faucet and not dripping through the valve. It drives me crazy also but then I remember that I have beer on tap at my house and get over it.
Do rear-seal faucets not drip a few drops after the pour?
All of my 525ss Perls drip three drops, one almost immediately after closure, one a second or so later, and that last one that tests my resolve to wait it out
It's possible the steeper spout angle on the 600 series lessens that to just two drips, but there's no way for it to be zero. There's too much wetted surface between the spout seal and the end of the spout...