Lexan will take the biggest impact. But it can be melted with a Bic lighter. Lexan only has a 10year warranty against yellowing,the same as 20 years ago. It is hard to clean and will scratch. A piece of
48"x60" Lexan needs 3/4" edge engagement and a 1 1/16" deep rabbet. So you better build a good framing system. Don't for get to ventilate the system.Lami looks better. Won't yellow. But is heavy and should get a frame to hold it. If you frame it properly you can replace broken pieces without removing all the glazing. It has a higher R value, has more sound deadening and cuts out 99% UV light. It's not as strong as Lexan, but it takes a heavy rock to break a car windshield, and it still does not hit the driver.
The pricing for either one is about the same.