I actually fixed one of my handles with it. Not on the grip though. the cork on the screw lock that holds my reel busted and I covered the whole thing with flex coat. It works great. I can tell you that despite its gloss, its not that slippery, but I don't know if that would be the case on the handle itself. I tend to hold my rod with my 2 forefingers on the screwlock, ring finger on the trigger, and thumb behind the reel and haven't had any slippage.......yet. Hope this helps.
Jay