We have three kids and my boys still fit in our rear facing seats but will outgrow them in the next year or two. So will consider trading for X then. I like the sedan. I came from driving an SUV and like that I can now reach the ground when I step out (I'm 5'2.) S has plenty of cargo and people room for our daily commute to school and for road trips. When we have guests or if one of the boys gets ornery, they get sent to the rear. I wouldn't recommend sitting back there for long trips (ventilation issues and all- many threads on this). I may be mistaken, but I don't think Tesla retrofits rear seats anymore.
We kept our 8yo Honda Odyssey (the dog car) so not quite in your shoes, but if all we had was the Model S, it would fit the bill for our family's needs. 3kids+2adults most days with squeeze room for guests if needed. (We also kept the 911 cab as the fun summer car but hubby keeps alluding to how slow it feels compared to my S85. It is the most impractical of our fleet as it can't even seat all members of our family. But heck.....)
good luck! Whatever you decide, I'm pretty sure your wife will find ways to drive the Tesla, so it won't sit in the garage lonely. (She can thank me later
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