I had a unit before.
1 bed room face to 東南 (L shape window) and 1 bed room face to 西南 (L shape window) .
In summer, the average temperature inside the room face to 西南 is 3-4 degree C higher compare with the room face to 東南.
In winter, the average temperature inside the room face to 西南 is 2-3 degree C lower compare with the room face to 東南.
I can't opened the windows of the 西南 room as it will be very windy (and cold) in winter. Therefore, I only open the windows of the 東南 room to get fresh air....