I got my first M35x, a 2006, back in July of 2008. It was an off lease car with about 21k miles and it was, without a doubt, the best car I had ever owned. It had the Tech and Journey packages in Diamond Graphite with Graphite interior. I drove and babied it for 10 years. I eventually decided to move on to something else and ended up with a 2013 G37 convertible. The convertible was an awesome car to drive - much quicker than the M - especially top down. BUT, as awesome as it was to drive, it wasn't awesome as a DD. At my age (then 56), it was cumbersome to climb in and out of and the doors were damn heavy and long.
I had given my 2006 M to my son and it was totaled 2 months later (not by him). I found an almost exact replacement in a 2007 - same color combo - but it also has has the premium package and the aero package. I don't think there was any other factory option available that it does not have and the prior owner did it a solid by installing the nav hack bypass using a slick toggle switch hidden in the cupholder. My son drove it for a year and change before he went to college as a freshman. I sold the G and have been driving the M since last August. It now has roughly 135K on the odo (had 119 when we got it) so getting up there in mileage and age. Been thinking about a replacement in the form of a smaller SUV rather than another sedan. Test drove an RDX, Lexus NX300, Infinti QX50, Mazda CX-5. All had good and bad. Even tried an Avalon in Touring trim, just in case I would stay with a car (don't laugh, the Avalon has a 301 HP V6 with an 8 spd tranny and it was rocket - unfortunately the seats absolutely sucked as the seat bottoms are way too short - even for me at 5'9"). None of the vehicles I drove were as comfortable as the M. Sure, some had Apple car play or wireless chargers and whatnot but the M still has features they don't - adaptive headlights, or easy entry with the moving seat and steering wheel when exiting the car. Hell, the RDX and Lexus only come with manually operated tilt and telescoping wheel. I switch cars with the wife all the time and never have to worry about adjusting anything other than the rearview mirror.
Long story short, unless I find something that truly wows me like the M still does to this day, I will keep driving her. I know some on this board have way more than 135K miles and their cars are doing just fine. I guess you're stuck with me for a while longer!