Radiator cap pressures. 7 lbs ok?

[Garfield2]

I have a 1996 Buick Park Avenue that I recently changed the radiator cap to 7 lbs from the original. Back in Nebraska my cousin and I always run the lowest pressure cap we could and increased the coolant glycol to make the coolant less prone to boil. Example, at 70/30 mix the coolant will not boil until 276 degrees F at sea level normal atmosphere. So at 7 lbs it has to be much higher than that to boil.

I've read that the higher the pressure is of a closed coolant system, the more efficient it is (faster) to transfer heat away from the engine and heads. Is this true? Doesn't really seem to make any logic. If the coolant is not at 200 degrees and not boiling, what difference does it make as it moves though the radiator and lets air exchange the heat.

We run the lower pressure to make it easier on the heater hoses and radiator hoses. It always seemed to give them more life. Rick has always run all his vehicles on the farm with the lowest pressure cap he can.

Are there any reasons NOT to do this?