The Harley stuff hasn't been fiberglass for quite a few years. Aftermarket vendors are all over the place as to both materials and quality. In just the last six months I've had my hands on both an ABS and a fiberglass tour pak and saddlebags of each as well.
The fiberglass pak I was messing with for a bit was surprisingly good for a fiberglass piece that you know is going to need final prep before paint. One of the saddlebags I saw (someone else's, not mine) was just terrible.
Of my own also recently got an ABS tour pak. Came from a place called Fairing Factory (I think that's right). Absolutely outstanding. I could not have been more impressed with the quality of the molding and the accuracy and precision of all the edge trimming and final holes drilling. Just a really really well done piece.