VW Golf 2014 and a VW Passat 2015.
If you find a demo car with the self-park feature, I'd suggest you give it a try and see for yourself.
I've run several of my own tests, for fun really. I sprayed water on an Audi A3 with the rain sensor and on my 500x. The Audi was nine times more responsive over the 500x's rain sensor, even in the "second" more sensitive setting.
I also drove the 500x and the A3 together with a friend, we found that the headlights, on the A3, would turn on immediately upon entering a tunnel, while the 500x would delay by about 5-8 seconds, at which point it we had already exited the tunnel.
I did the above tests because compared to my other cars, those sensors seemed rather "brain dead", and I managed to prove that they indeed are a bit "slow" to respond compared to the A3. The VW's have been graciously provided by friends who own them.
Nothing serious really, it was just a fun afternoon to play with the 500x.
PS:
My Smart car has an even worse rain sensor response....