Yeah, it's one of those things that I got to using once after getting frustrated trying to get my normal usernames working, and now I don't want to have to remember username *and* password for every forum and whatnot I'm on.
Anyway. You mentioned about a fast reacting Bosch PWM valve, and wondered if the Bosch valve is similar to what you were talking about. And I just sorta noticed it looks a little similar to the Subaru control valve prior to the rocket, and wondered if theirs is essentially something on the order of a custom built version. That part number I listed is one example of it; apparently the port size is something like 3/4" (19mm) so it should flow enough for some purposes.