Rating: Complete thumbs-up. Polite (and not in that passive-aggressive "judge way" -- "Do you need more time to prepare, sir?" -- but actually polite) and explained his reasoning clearly in the cases that he heard. (And, for the record, I've only appeared before him once, on the morning of April 1, 2002, and he ruled against me in 2 out of the 3 cases that I brought.)
Since John O'Brien was serving as a judge pro tempore that day (i.e. temporarily filling in for the regular judge), at one point he asked what the other judges in Bellevue District Court had ruled, saying he wanted to be consistent with them. While this sounds unremarkable, it's actually a good sign to hear a judge ask this, because it means they have a realistic view of what they're doing: One person, who has the best training in the room but is not infallible, using all available resources -- including the person standing before them -- to try and arrive at the correct answer. More often, judges will start the hearing by ruling on the case without allowing the plaintiff to speak, or cut people off to stop them from bringing up the judges' own past cases, or start the hearing by ruling on the case without allowing the plaintiff to speak, or leave to go on vacation before the plaintiff's deadline for submitting their argument, or start the hearing by ruling on the case without allowing the plaintiff to speak. (And since the judges' "pre-emptive rulings" frequently contradict each other, it apparently doesn't work for arriving at an accurate conclusion.)
Mr. O'Brien ran the courtroom about the way that most people probably imagine they would do it, if they were drafted to serve as a judge for one day, and weren't in a bad mood. (And that was more or less the case anyway, since Mr. O'Brien is a lawyer and only occasionally serves as a judge pro tem.) That is a good thing to say about a judge.
John O'Brien also has a profile on the Web page of the O'Brien Law Firm in Issaquah.