Your friend should rethink his choice... fiberglass/synthetic handles do not belong on striking tools.
Not only does fiberglass transfer far more shock and vibration to your body parts, it also allows the striking head to recoil a lot more. Shock, vibration and recoil translate into lost or wasted energy. A fiberglass handle requires you to use more energy to accomplish the same task... while increasing the beating your wrists, elbows, shoulders and back take even more. A fiberglass handle means you will work harder to get less done, all the while unnecessarily abusing your body.
Try this experiment...
Take to hammers of the same weight and handle length, one with a fiberglass handle, the other with a hickory handle. Hold them loosely and strike something solid with each, such as an anvil or the flat anvil of a large bench vise... it ain't necessary to strike them hard, more or less just let them fall of their own weight. Which one recoils (bounces) higher than the other?? A lot higher?? Next try holding one in each hand a strike the two heads together (be sure you have a firm grip on the fiberglass handle‼).
Guess why most fiberglass handles have a rubber, or synthetic grip on them?? It's because of the increased recoil and vibration (energy loss).
With a hickory handle the proper technique is to release, or loosen your grip just as the head strikes... at that point, the point where the tool strikes, it does all the work while transferring near all the energy to the object being struck. That technique ain't possible with a fiberglass handle, the tool will bounce clean out'a your hand... fiberglass requires you maintain a firm grip, as well as muscle force all the way through the strike. Fiberglass handles on striking tools are nothing but a sales gimmick... an "unbreakable" or "lifetime guaranty" sales gimmick. But longevity, or perceived longevity, don't make something better... it simply makes it salable to the naive. Shock and vibration to the body is cumulative; it may not feel like a big deal on the first strike, but three hours later... or three years later...
Using a hickory handled tool also allows a lighter striking head... my favorite nail hammer weights 13 ounces, not 16. My 13 ounce, hickory-handled nail hammer will out-work a 16 ounce, fiberglass-handled hammer all day long... while, at the same time, using far less of my energy, and being far less abusive to my wrist and elbow. A 6# hickory-handled maul will transfer as much (or more) energy to the wood being split than an 8# fiberglass-handled maul... and beat you up a whole lot less.
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