Anyone replaced a Escort Mk II rad with a Polo rad?

I heard the polo rad is lighter but its it worth the change?

BTW, going on a 4AGE 20v.

do it its alloy and better at getting rid of heat

Definitely worth the effort - the polo rad is aluminium , so cools a lot better

I have a polo rad in my Locost...

do polo radiators need a seperate expansion bottle?

Yes, they have only a bottom, top and air bleed (8mm ish outlet) connections, no rad cap.