I have a 2009 euro outback with 2.5 (this is the 03-09 series) and parking sensors mounted to the back bumper. Now I want to mount a towbar but not sure if I must get one with removeable head. From a price point of view I want the fixed head, also other drivers on the parking lot will be a bit more careful then  .

Does anybody have experience with fixed towbars and parking sensors? Any ways of testing if a fixed head would work? (I was thinking to hold a screwdriver from the trunk to see if it activates the beeps).

A friend of mine used a toilet paper roll and a tennis ball with duct tape to simulate one on his Ford Escape. For what it's worth he had no trouble on his Ford.

Because of the proximity to the car the parking sensors will not notice a tow hitch unless it is high mounted or inordinarily large.

Parking sensors are sonar based, and the tow hitch is generally between the waves of the center sensors where it can't reflect the signal back.