I've driven VWs for decades. I've had my current '97 VW GTI-VR6 for ten years and I've never experienced any sort of electrical problems. But bashing/defending VWs is off topic for this thread.
The following is a taken from the Shine Racing Suspension site and is directed at primarily VW owners but seems to be relevant here since Subaru also uses MacPherson Struts.
Why Not Lower My Car?
VWs use a MacPherson Strut <http://en.wikipedia.org/wiki/MacPherson_strut> front suspension. The MacPherson design is extremely sensitive to ride height, and only really works at or about the factory ride height, when the control arms are level.
There are two critical geometric points to consider when discussing suspension performance: the center of gravity, and the roll center. The distance between these two points (the roll moment arm) determines the tendency of the car to roll.
The center of gravity moves with the ride height of the car. Lowering the car one inch will drop the center of gravity approximately eight tenths of an inch (only the sprung portion of the weight moves downward). The location of the roll center is a function of the suspension geometry. Lowering the body one inch on a Mk4 VW lowers the roll center approximately one and a half inches.
As a result of lowering the car 1 inch, the roll moment arm has increased more than half an inch, making it much easier for the car to roll.
When a car is allowed to roll, the resulting weight transfer decreases the available grip and keeps the car from handling to its potential.
So my questions is how much if any can a Legacy GT wagon be lowered from stock ride height before the control arms are no longer level and the handling is adversely effected?
The aftermarket wants to sell product so they will gladly sell you lowering springs & struts even if it adversely effects handling.
They know that the majority of owners who spend all that money to make the change won't admit if the handling has changed for the worse. Too many car ethusiast would rather look good than feel good.