Hi TP,
My understanding is that old school copper and brass radiators such as in P6/P6B are more efficient at keeping an engine cool than a modern aluminium alloy radiator, of the same dimensions. Modern radiators tend to have plastic end tanks, so ensuring that they are earthed is very important, otherwise stray currents can very rapidly see their demise.
When I had my radiator recored recently, sitting on a display was a large aluminium alloy radiator, in this case complete with aluminium alloy end tanks. It looked very fancy, but when I asked the fellow about it, he said, they're made in China, basically they're rubbish, not a patch on your (copper and brass) radiator.
Provided that you use a suitable coolant and change it accordingly, (don't leave it in there if you only drive, as an example 1000 miles per year), the cooling system will remain healthy.
Ron.