I just typed a decent reply but Safari crashed and it’s gone
The summary was something like this:
They obviously aren’t more efficient at their given task. Horsepower gains are had when the system runs cooler, so if they don’t have any horespower gains then the system isn’t running cooler….kinda the point of a radiator right?
What governs how cool your system runs be that minimum temperature?? The thermostat does its biggest job is to maintain a minimum temperature to run the engine within its most efficient temperature range, so it will only go as cold as your thermostat min temperature these will do that much better as I am sure you understand cause when the thermostat fully opens and more cooling is needed they will have the extra ability because of the quality of the cores and build, if I removed the thermostat the whole system would flow better faster etc but as I am sure you learned once you can pass coolant through a radiator to fast and reduce the ability for the radiator core to cool the coolant. To run the engine to cold also increase your engine wear rates as again I am sure you know
That probably explains why they’re cheap also 
They arent cheap they are cheaper then standard but I already explained that