Mine is louder than other legacy as well, but not by a lot. Is the dealership helping you? The technicians are a little deaf, banging on disc brakes everyday in a shop.
I have found the same comments on the Outback forum, same generation. I guess there is some inconsistency in the weather strip quality or in the way the door and window are put together. Parts are the same from one car to another, it should be as quiet, I'm still searching the problem on mine, it also makes a whistle noise on that B-Pillar when the car is wet.
Anyone knows more about that issue? That would be great!