I have 2 my Model 3 LR RWDs with both on stock Primacy MXM4 235/45/18 and were getting 244 and 253 Wh/Mi efficiency over 30k miles each.
I recently changed to Pilot Sport AS4 235/45/18 and over 5000 miles on both cars they are getting about 285 Wh/Mi efficiency which is 16% and 13% less efficient. These tires did cost about 25% less than the stock tires so the trade off is probably worth it.
But this made me wonder if there are more efficient tires that I should be considering for my next set of tires? For reference, I live in southern California so I don’t need winter tires.