My trailer is 15 years old, has a front window protector made with a metal frame with thin fiberglass panel as protection. You can see it in my signature picture just under the trailer name on the front (in blue).
It has traveled all around the US with 15 years of travel between Michigan and Florida or Texas each winter. It has never had a ding or hole from flying rocks or anything else except bugs. The main use for the cover is as an awning over the window when parked.
i would not worry about that window up front.
Barney