And supercuda....the water and coolant used will be the same in both a brass or aluminum radiator so that's not even relevant for comparison purposes.
Your whole supposition is that aluminum is better than brass because it has sslightly better thermal conductivity, the difference in thermal conductivity between water and/or brass and aluminum is orders of magnitude, the restrain on the transfer is the water's ability, not the brass or aluminum's.
It's like arguing that 5/8" fuel line is better than 1/2" because it flows more, into a BBS carb. Irrelevant.
