Our house is peppered with these, and has survived the last two Florida hurricanes, not necessarily due to the header bolts, but it's a factor in the installation of Hurricane Fabric. I consider the fabric to be a suitable option to heavy plywood panels for a number of reasons.
They are a bit easier to install, especially if you have the header bolts already in place. Time consuming to attach the grippers to the fabric, but that has to be done only once.
The individual panels, once cut to size and grippers attached are quite light weight and fold for storage.
The fabric resembles un-tinted trampoline material, although I suspect it's a good bit stronger. The ad copy states that it meets Dade county hurricane code, which might be the most severe in the country.
Our 3 bedroom, 1600 sq ft house panel collection, including one for the two car garage door stores in a space smaller than a typical dorm or office sized refrigerator.
I think these are competitive with plywood, perhaps a bit more expensive, but so much easier to store, install and uninstall as to be incomparable.
I'm not affiliated with the company, simply a satisfied user. I believe one can order directly, as we did, or from The Home Depot, as they had displays in their store two storms ago.