Just been thiking about this for a few days!

and imho if you will only ever run 15psi no higher...then why spend absolute loads when (sorry to offend) a pace double size is quite adequite (spel) ...im running 16psi through mie and have been all summer!

Then you wont have to worrie about water temps cus the rad is still open! and you can use ya standerd fan!

Im thinking of pumping my boost up to 18psi soon,so thats the only reason im thinking of getting a bigger cooler! and im goin with a rad tec! cheaper than the GRS and pro alloy and will cope with 24+psi! (tho no disrespect to the aforementioned companys! as im sure the grs and pro alloy are good good coolers!

If i was to choose between grs and pro alloy i would go with the pro alloy! purely on the fact that not everyone has one! and the shape leave some of ya rad open to the breaze,also with the turbo cooler option water temps should never be a problem!

Hope this helps!

also hope it makes some sense!