Actually, #3 is incorrect. The cooling system see a maximum of 7PSI when hot.
Freezing point depends on whether its NPG or NPG+. I've had the coolant down to -20 and it worked fine.
The 7psi claim does not make sense its not like the liquid can absorb the pressure your max pressure is still whatever the cap blows off at.
It might not expand as fast as normal coolant and stay under 7psi that way but there is nothing that can limit that.