Depending on who you ask, you'll get a lot of different answers because test prep is so results driven. You'll find parents/students will love/hate each and every program. I think part of the "right" answer comes from who your kid is as a student and where he is at prep. If he's your usual cutthroat, Irvine kid, then he will probably do ok at/benefit from one of the big SAT prep factories in Irvine. These type of classes require a lot of student driven motivation and a lot of the improvement comes from peer pressure (seeing other kids improve, posting of scores, etc). If your kid is behind in any way on concepts, has trouble with standardized testing, needs a lot of coaching/motivation, then one-on-one type tutoring may be the way to go.
If you go the Asian SAT prep factory route, I would pick a place that has developed its own SAT prep curriculum and has quality instructors. However, I would avoid places like Princeton Review/Kaplan b/c most of their prep is gimmicky and honestly, you can just buy their books and prep at home.