I currently have a P85 on order with the 19" wheels. Given the alignment/tire concerns with the 21"s, the fact that the 19"s are already pretty big, and that according to this calculator (http://bndtechsource.ucoz.com/index/tire_data_calculator/0-20) the contact patch on the 19"s is actually bigger than the 21"s, I decided to stick with the stock 19"s. Unfortunately, these get saddled with all-season Michelin rubber (on the S85/P85) when the 21"s get max performance summers. The concern a poster on the Tesla manufacturer forum brought up was that generous application of throttle anywhere between 0 and 50 or so caused squealing and traction control to kick on. Further, given this, was some thought that the P85 is probably no faster than the S85 so equipped. Any thoughts from current owners on this? I've discussed this quite a bit with lolachampcar with the general advice that 19"s with better tires is the way to go, but given that I have to take the Michelins is it going to be miserable on them until it's time for something new? I hadn't planned to swap them out immediately, but that may be my only option (anyone want to buy a spare set?). Would I be better off requesting Tesla install the high performance Goodyear all-seasons they put on the S60 (the Michelins are touring, the lowest-performing category)? Off the line, sure, I totally expect some wheel spin on all-seasons. At speed? To me that indicates some tires that need to be swapped out for something that performs better. To be clear, I'm OK sacrificing some range and ride roughness for handling, and would have preferred a summer tire of some sort if it were an option. Thanks!