I have worked with them. They are professional people, though a bit on the pedantic, perfectionist side. But they get the job done. Not like Ah Nehs or (some) Pinoys. And they aren't the backstabbing types. Japanese employers are also more reluctant to retrench workers during a recession; they value loyalty. Not like the trigger-happy Ang Mo employers.
And no, they aren't racist, if that's what you're implying. There may be communication issues, as their command of English may not be very good (blame the Japanese school curriculum for teaching English poorly). If you know the Japanese language more power to you.