[TXSchnee]

I had an F15 xdrive35i (M Sport) and currently have an '18 M40i with the 20" set up and adaptive dampers. It is a bit rougher than my X5, but I actually find it pretty comfortable. I avoided the ventilated seats, even though I am in TX, due to the lack of bolstering. I personally find the standard sport seats very comfortable, have done long road trips (over 1200 miles) and have never had any back issues. All that said, comfort is entirely subjective and I would definitely advise test driving.