I came from a 650i that had a rather harsh ride, without the great handling of the 997S. The run flat tires probably had a lot to do with that. This is now my third Porsche daily driver, and I don't find it uncomfortable in the least. I rarely engage the stiffer setting of the PASM, as I also have an ECU tune. The stiff setting feels like it's going to shake my fillings loose, and I just don't enjoy it around town. Fortunately, it's selectable, and when It's not engaged, the car handles beautifully, and comfortably enough.

 

I went form MB S550 to Carrera 4 997.1 as a DD. it was very hard road getting used to it but when that engine starts and you shift through gears it makes up for it.
In my opinion it is a stiff but not harsh ride. if you enjoy what the car is built for you can get used to it after few months.
I dont think you can compare it to a BMW in ride softness unless you are looking at M. I can compare to a 330 with sport package and a 550i and those cars are way softer.

Again, it is something you can get used to and not even notice after a while. Get nice tires (DWS or SSP) and 18 inch rims and you'll be set. It will be softer.

I my self still want a touch softer ride when i need it and firm it up when i want to play so i'm trying to get PASM retrofired on my car. PASM in normal mode is a touch softer than Non-PASM suspension. I've driven both back to back and although i liked PASM stiffness (or softness in this case) i could not afford it at the time.