I brought my 2 week old MX to resolve some issues. The loaner was a 2013 MS 85 with 17k miles. I've also had a '16 MS 70D. Wife was a little disappointed at the "downgrade." The point of the post is to share my opinions of the 4 year old MS loaner vs. '17 MX vs. '16 MS. Overall, I have ZERO regrets on the MX. The MX has the seemingly unnecessary, but awesome features that make it feel like a spaceship. The '13 and '16 MS were awesome cars, but I get the feeling of a downgrade when driving the MS because it isn't a spaceship like the MX. That said, I'm pleasantly surprised in the relatively early MS. For $50k, I don't think you can get a better car. I'm actually contemplating buying a CPO MS to replace my other car. Other details: - Crazy FW doors, automatic doors, cockpit windshield, phenomenal seats, etc are what gives the MX the edge. Those seemingly unnecessary features give me a different impression of each car. - MS appears to turn more heads than the MX. I personally think the MS is cooler looking than the X... until the MX FW doors open. - I like the way the MS drives slightly better than the MX. Sports sedan feel. MX is extremely close though, just higher off the ground. - I noticed that the '13 MS uses far more energy per mile than my MX. I'm driving it the same way, it just uses more per mile. The '16 MS used about the same as the '17 (non-P) MX. - The interior of both the '13 and pre-facelift '16 are nice, but they feel cheap compared to the new MX. They definitely improved material quality. The obeche matte is of poorer quality in the '13 MS. The soft touch vinyl/plastic has been upgraded as well. The cheap aluminum appears to be the same in each interior. It appears to be vulnerable to dings and dents. - Judging from the '13 MS, Tesla was doing things right from the start. They have improved that car tremendously, but the '13 is still an amazing car. Tech has improved drastically as well. - I'm 6'1", the MX has better rear view mirror visibility than the MS. (not with the 7-seat version) - Retractable door handles feel a little cheap compared to the push button MX. - Getting into the MS is more difficult than the MX - and I'm a young, able-bodied person. - '13 MS seats look terribly uncomfortable, but they feel ok. The MX and new MS seats look great and the feel amazing. - '13 MS w/ Nappa smells like an old catchers mitt... not necessarily a bad thing.