I've done some reading after I posted the question above. I think the primary variables are load rating of the 21" Tesla wheels (aka who knows) on the heavy model X as well as challenges in matching the wheel/tire outer diameter vs. the stock specs. As I have personally experienced on my model 3P, if things are matched really closely you can expect traction control as well as other problems.
Thanks for the very clear answer -- long term not a good idea to use 21" Tesla wheels (intended for model S) on the model X.
Thanks for the very clear answer -- long term not a good idea to use 21" Tesla wheels (intended for model S) on the model X.
