IMO taller sidewalls to improve ride are not a good idea since tires are a critical component of handling. Components are 'matched' to achieve a certain handling capability.

One never knows when it will be necessary to make an emergency avoidance maneuver. The additional rollover and potentially a higher center of gravity from taller sidewalls could be the difference in the outcome.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas