I know the bolt pattern is the same but I'm not sure about the center bore and offset. I see aftermarket wheel companies cross-selling wheels for both the model S and the model X so I'm assuming it can work. I'm also thinking the 19 x 8.5 with a 265 – 50–19 tire on all corners would be the range king with a LRR tire. I suspect we will be able to pick up 19 inch slipstreams fairly inexpensively soon since a lot of model S's are shipping with them. Tesla claims 2 to 3% range boost on the model S.