If you go the E46 M3 wheel route, the upper surround with the controls in your current wheel will transfer to your new wheel. I am not sure that is the case with later M3 wheels.

There are also shops that will recover your existing wheel and add thickness and thumbrests. That means you can buy a used steering wheel and have it redone the way you want. Some will also flatten the bottom of the wheel. Going that route your total investment might still be less than a new steering wheel.

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