Harleys will always be subject to bashing from some parts of the Guzzi fold- I think it has more to do with the image than the dynamics of the motorcycles.
I have never ridden a Sportster but have nothing against them. The big twins are decent touring bikes but I agree with Ben about the brakes, although the models with twin discs are acceptable.
I've tried one, found it was not right for me and sold it on again- maybe in about 10 years I may fancy another.
Guy