My first Tesla was a 2018 Model X Performance. The first thing I noticed between 2018 and 2019 the range was increased (but has now decreased from (320 to 295 miles
and the home super charging speed was 80 AMPs, which has now been reduce (I am told because of overall safety concerns) down to 48 AMP's. The new suspension I believe is quieter and I have been told tighter but I never tested the 2018 in the 1 month I own it. I have a 2019 Model X Performance now. It was delivered in June of 2019. I have driven it nearly 18k miles since then and my first trip was a total of 4500 miles 3 days after I took delivery of it.
I live in Satellite Beach, FL (just south of Cape Canveral) so we get a lot of sun. I can say I have never had a climate control problem (I am only the only person in the vehicle). I did purchase all of the sun screens and will say the sun screens for the front glass do an amazing job of reducing the bright sun beaming down during the hot summer days.
With respect to the road noise, mine is exceptionally quite, and one of the many reasons I bought the suv (I came out of a Mercedes Benz suv). I will say, when driving very slowly, I do have a creak from the front right suspension and only can be heard with no radio and less than 5 mph, yet they can find it.
Also the 2019 no longer has vented seats...straight leather...while very nice in Florida cool seats are amazing!
My biggest complaint and only is the wipers...When traveling at highways speeds (65 mph plus) while raining, the wiper blade on the drivers side literally goes off the windshield and bangs of the left pillar when coming back onto the glass. Their is no damage and Tesla has attempted to fix it twice.
I hope this helps and good luck.