Rented and early build model 3 back in feb. for 2 days off of Turo, the car was on 18's and the owner had the tires over inflated (51 psi) at the time i really did not think of lowering air pressure and i drove the car from irvine to san diego then to long beach and back to irvine, over 300 miles, my wife and i loved everything about the car except the rough ride, it was a deal breaker for her and i had to convince her that i would put softer aftermarket springs on the car, she let me know that if we could not get a much better ride than this would be my car and she would be going back to BMW.
the car we rented drove like it was on rails but tires lacked grip and gave out WAY before the suspension budged
I ordered our car with the 19" sport wheels and when we drove off I was expecting the car to be similar to what we rented
but it was NIGHT and DAY different, the new suspension soaked up the bumps and road irregularities were so much more damped that we could not believe it was the same car, (our tire pressure was 42 psi so I'm sure that had something also to do with our ride quality) tossing the car into a corner hard there is a little more body lean and you can feel the rear end move a bit more but with our 19" stickier tires the car corners harder than our rental did and when people who want a test drive ask how it handles they grin ear to ear after taking a frwy. on ramp when i push it hard.
unless you are a gluten for punishment i feel you would be much happier with the new suspension but if you want to up the handling then there is always the coilovers and the suspension mods from mountainpassperformance.com
oh and the little woman, after calling me crazy for standing in line 4 hours over 2 years ago she informed me she will be keeping this one and if i want one ill have to get my own! she can't quit telling everyone what a great car this is and how everyone should be driving one, good thing i made 2 reservations!