I would like to relate to me experience using Nissens brand.
I just got back from Bayernz workshop Bukit Mertajam, Seberang Perai yesterday. I replaced my cracked radiator few months back there with Nissens made in Denmark. Few weeks ago while servicing my E39, I did my regular tour undercarriage and found the white spot bottom join area of the radiator. Coolant leaking sign. Called Bayernz ask whether there is warranty and they said not official but willing to rectify it at no cost. Upon arriving there yesterday and they confirm my leaking finding. They try to change the rubber seal/o ring i was told. After one hour doing it outside and fix it back, water still dripping. They decided to change to new one. This time brand Behr made in South Africa.
I'm back in Ipoh now and still monitoring the water level and any 'hissing' sound while engine is hot. back to Shah Alam tomorrow.
I must praise Thomas and Bryan of Bayernz for their commitment and responsibility to resolve the issue. Some may say they charge higher than Happy Motors etc but I'm happy with their service and the workshop is presentable.They specialise in BMW and Mini.
Since they remove the radiator and the fan, I decided to replace my aging clutch fan as well. So no workmanship charges apply. In total I only pay for the clutch fan.
Nissen radiators are good, the core is actually thicker than Behr. As for price slightly cheaper also.
The local agent is in Kelana Jaya, behind the LRT station. The boss is Mr. Moo (same row with the famous pork noodle corner shop).