Well, I'm in the same boat. About 3 weeks ago I got the "look alike" filter for the Golf / Jetta from the dealer. Looks right, fits right, but there is a problem. When our Van sits overnite, the G/J filter apparently drains itself due to it's not-intended mounting position. How'd you know that the only difference was the postion of the check valve? Is this a.k.a. an anti drainback valve? Cold start the next morning is just like after an oil change (if you don't pre-fill the filter that is), a second or two of clatter from the mains while the filter fills up. Makes me shudder. I also found that the part number from TiiCo is no good in the USA. Even had an import parts guy try a cross reference...nada. If I'm correct that other filters are allowing a no oil pressure condition at start, all of us TiiCo users have a problem!