We have the Rear-Facing Child Seats and love them 85% of the time! For our twin 6 1/2 year old boys, they're almost perfect. That said, have some questions, thoughts, comments (borderline rants). First, these are awesome because the kids stay out of the main cabin area most of the time. They can eat crumbly snacks and drink water (only) without fearing the 'mini-van effect' in a $100K car. Love that! Was it worth $4K? I dunno. That's hard to justify but it looks like there is a decent market for selling them once the kids grow out of them. We purchased an inventory model that already had the option installed but if we had to actually select it, we may not have. Ultimately, I'm glad we have them. Heat is a big issue and as many have suggested over the years, tinting is a must. However I still can't figure out where the fresh air comes from when I set the HVAC to fresh air. I looked for the vents that some have posted but could not find them. There are slots in the underside of the molded upholstery above the rear wheel well area, but when feel behind the fabric slots, I feel hard plastic, not vents. Any ideas where to look? Pre-cooling the car is 0% effective as you lose all of the rear cooling when you open the hatchback to put the kids inside. Also, and here's the rant piece, what's up with the single cup holder between the two seats? There appears to be space for two but there is only one, and then an odd shaped hole for small things like toys and such. That is a head-scratcher for sure. Aside from that, we do really love the rear-facing seats. After 8 months in our Nov 2017 Tesla, the novelty has not worn off for the kids and even in the bay area where every other car is a Tesla, other folks are still surprised when they see them.