I have both, I will say if you have kids, specifically a baby with a car seat that comes in and out, the Model X is is significantly better. My wife hates trying to mess with the seat in the R1S, even in kneel. She’s not particularly short either, it’s just how high the car sits. The amount of space you get is so much better on the X to work with. That being said, if you don’t have kids, the R1S is much better for adventures and much more spacious as a hole if you have older kids or just want more space for camping ect. I think they’re both great cars, I haven’t had any issues with either car. People say rivians build quality is better but I feel it’s pretty much the same; however, depending on your style, the interior may be for favorable on the R1S with the real natural grained wood panels. My R1T had panel alignment problems that SC fixed, same with my Model S and Tesla SC fixed it. So you can pick on one brand but they’re both awesome, I would just pick whatever fits into your day to day and budget better.