Don't know about the 3x ED barlow but I have the 2" 2x ED and I am quite impressed with it. No ghosting/reflections even on a bright object like jupiter. One would assume that if one product is of good quality then the other products from the same manufacturer would also be good, but this doesn't seem to apply to GSO. Some of their things are great (ie. Scopes) and others are not so great (ie. 2" superviews). Hopefully someone will have the 3x and will be able to tell you something about it
Leon