In terms of radiator Ron Davis does some cool stuff.. BUT.. I really like the radiator/core support combo of the Autorad.
Mainly how it can be so much larger.
If I was just buying the radiator and cost wasn't an object I would get the Ron Davis.. if I wanted the system I would get the Autorad.
Also, if I was doing an intercooler or something special I think Ron is better are custom stuff like that.
Both will surely keep you engine cool