I think the Behr radiators are now made in the third word, where lower QC is generally the rule, so I would go with the Nissens now, they are from Denmark, I am told.

That said, at 75,000 miles I got back around 1997, a new Behr radiator, on the assumption it was just normal routine maintenance to replace it, from a Mercedes Benz dealer in Marin County, California. In those days Behr was the thing to get, according to list serve (early internet discussion fora) MB owners.

12 years later, with 161,000 miles on the car, and some 30,000 miles coolant replacements, it's still working just fine!!

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)