I honestly looked at the imported alloy cheap ones which would have been good
but after some issues in trying to import them going through the middle men
It became a headache with numbers and postage options. I even drew it up very
carefully in Illustrator and started a thread as a group buy.
Im not cut out for business as Im too all over the place and indecisive.

Anyway, went to a radiator joint in Keilor Park that had been there for about
30 years or more and couldnt be happier with my copper 3 core one which was quite
a good price and great service. The thing is they told me that business was slow
as many go alloy these days and the old dude couldn't compete with imports.
Went back the other day to get another made for my CA18 and the joint was gone.
Im not saying this is what you should do but copper is a great material and
although heavier its easier to repair and can support a local artisan from retiring
if you are willing or able to spend the bit extra as Nick has stated.