MG senior golf balls are illegal because they do not conform to the USGA golf ball speed limit. Therefore, they are illegal to use. According to some testers, these balls can travel up to 15 yards further off the tee. They are also 75% self-correcting (prevents slices and hooks). The USGA states that the initial speed of a golf ball can’t go beyond 250 feet for faster than 76.2m per second.