Golf-ball sized hailstones are unusual and likely outside the design space. Crazy that people were concerned about "chemicals leaking" -- do they think the panels are full of goo?
Golfball size hail storms happen all the time around Dallas. I'd say baseball size hail is unusual. Only 1-3 storms a year around the metrolplex. And grapefruit size hail is rare (thankfully! One hit the suburb next to me a few years ago and hailstones penetrated people's roof, went through the drywall into their house!)