There is no "model year" in the Tesla world - Tesla improves ability of their cars using over the air updates and offer new hardware, when they are ready to roll out. It's always wise to buy the car now, otherwise you will never stop waiting for the next major improvement. But there might be a different situation, if you have the choice to decide upon the date of replacement. Should our fleet management opt for a three year-leasing or four year-leasing? In our local market, three year leasing of business limousines is supported by local manufacturers heavily. They not only tend to color their portion of air polution, they like to push registration statistics. So the usual rule is: three year leasing costs less than four years. Tesla is different, returning the car after three years instead of four costs a significant premium. Will tesla still manufacture the model X in three or four years? Very likely, if they accomplish their mission until than and survive in a hostile surrounding. Will it take three years or four, until many small steps add up to a major leap? There is plenty to do: - a more mature set of sensors, bringing autonomous driving closer to reality. It's not only a second color camera. I am worried, that Model X is equiped with a single, front-directed radar only. On a German Autobahn, you need to observe front traffic and trunk companions with same, high attention. Changing lanes here, you need to add backwarded radar to detect fast approaching cars from behind. Even if you keep your lane, it might block faster cars, that are not allowed to overtake on right-sided lanes. Autonomous cars, being nearly blind to the back will not be fun cars in Germamy. - an enhenced choice of battery and charging options, offering more range and enduring high speed travel. Today, a Model X might be the stop-and.go champion with highest acceleration. But I guess I cannot go 210 km/h travel speed on light traffic for a long distance. That's BMW and Porsche territory. - a simplified user interface, head-up-display technology or something similar.