We receive the chairs. They were not packed as well as I would’ve hoped. We were missing the rubber stoppers and the rubber rings needed to put the chairs together. I’ve emailed the company to get those Shipped ASAP. Otherwise the chairs look very nice. It was hard to tell online, but it appears the main difference between the plastic and the fiberglass is that the plastic or more matte finish and the fiberglass is glossy. There’s no evidence that it’s fiberglass like in the original Herman Miller chairs where you can see the crosshatching of the fiber.