We have air con throughout our flat, we have it mainly for the heating in winter as its very cheap. It is a properly installed system with units on the walls. Temps and humidity like this I am greatful for it! 22C here in Leeds still at this time according to my thermometers and inside is also a nice 21C 50% humidity perfect for sleeping.
All day it has been 22C indoors and 30C outdoors! Has cost me about £1 in electricity for the whole place to be lovely and cool.
We used to have the portable units but they struggled to cool one room and would cost about £7 a day to try to cool a room with all the internal doors closed. When you have the hose sticking out the window you are sucking warm air back into the room from outside to replace the cooled air it is sucking out of the room to cool its innards!