you can get away with the lower number if you are not runing higher speeds. However you can go inbetween the two numbers if you travel at higher speeds. just if you get over 100mph i would use the high tire pressure but understand your tire wear will be different and faster.
Enjoying an E89 Z4, F30 320i and Fiat Pop 500 //
E85 Z4 (sold), E82 128i (sold)