If mini reversing contactors are rotated 90° the following will happen:

DC operated:
Undervoltage is reduced from 0,8-1,1 x Us to 0,85-1,1 x Us
Mechanical and electrical life will not be influenced.

AC operated:
Undervoltage is reduced from 0,85-1,1 x Us to 0,95-1,1 x Us
Mechanical life is reduced from 5 mio. to approx. 2,5 mio. operations.
Electrical life will not be influenced.