You need to be careful with stray current in alloy radiators, it can destroy them in no time. Good coolant should be used too.
You do get what you pay for though.
When the radiator went in my eg i was told to just get the Koyo standard replacement by the radiator guy i use. I wanted the Koyo fabricated radiator, was advised against it as they are difficult to repair and cost a lot more.

Here is a link on how to do a stray current test, fact sheet 119
http://www.nulon.com.au/support/factsheets/