Weighing in at only 30 grams each, these legs will help lessen the impact of most hard landings and generally decrease vibration damage to instruments on the vehicle. This also increases ground clearance by 2 1/2 inches. Spring-loaded toilet paper holders are fairly ubiquitous in America, so Brits and most Europeans are SOL, as their TP dispensers are only metal poles with a tiny balls at the end. Asia might be the same. I'm not sure how common Wiffle balls are overseas, let alone golf ball-sized ones. But as necessity is the mother of invention, I'm sure they will prevail. Also, ping pong balls are the right size, but shatter easily.
The fat end of the roller is right up against the arm, so I put two layers of shock absorbing foam in between. There's a small protrusion at either end of the roller (to keep it in the holder), so slathered it and one of the holes in the Wiffle with rubber cement and merged them. It's best to use a flexible adhesive as crazy glue or any cyanoacrylate will snap the moment angular pressure (i.e. landing) is applied. A binary adhesive will surely bond them, but may turn the Wiffle ball into a Wiffle puddle.