The dealership always keep the PSI on high to prevent the tires from developing square spots (lopsided).
I usually set the front at a higher PSI than the rear. On my New Beetle and Mini, the front is set at 33-37 PSI depending on how the tire looks and drives. Just use your observation. If it doesn't look flat, drives comfortably and handles fine, then you're good. Usually higher pressure yields better gas mileage at the expense of ride comfort.
As for the rear, I set them low at about 26-28 PSI for comfort. Besides, there's much less weight resting over the rear wheels in a front-wheel drive car. The weight distribution of the Beetle is F/R 60/40.