I have had Maui for a long time great glasses. I currently for the last few years have had costa's, and there awesome sunglasses for fishing and being outdoors. That being said, I would lean toward the Maui's just because you are getting them directly from the source. The ebay dealer may be legit. It has already been mentioned to really check the reliability of the dealer. If he sells you fakes, call him out on it , which will effect his reliability score. Again, if your getting your hands on a pair of Maui's that are for sport/ outdoors, and not a casual pair, go with Maui.