I use UPS. They will find a excuse to not even pay the $100! I learned many years ago to value at $100 & no more towards insurance. I had UPS drop the glass box in Florida destroying a glass many years ago. They disposed of it in a dumpster at the plant, said it was delivered (NOT!). When I filed a claim got nothing. Learned a lesson & moved on. Just like when UPS drove a forklift over the corner of a double playfield box.
The excuse they use is the engineered box did not have a burst stamp on it, like standard size small boxes. Guess what the producers of playfields & glass try to get a well designed box or sets made to survive the handling.
Here we usually have the same UPS driver, & Fedex is 50/50.

When I first started shipping glass in the early days I used the postal service. One of the multi glass box was destroyed again to Florida. Looked like a steel pipe burst through the side of the box. Denied claim. On the + side PBR sent my last order to my old house address. It eventually got returned to them almost 3 months later.

Had glass (4) for Marco Specialty. No sign of Fedex picking it up Friday or today. Took it to the plant myself this afternoon. Pretty shitty service compared to UPS.