There's a little trick to making sure you're getting the best paintballs for your paintball marker, and it takes hardly any work, except maybe hiding from the department store employees! The tip is to open the packaging and remove a couple paintballs. Then find a flat surface in the store and roll them to see if they're smooth or have dimples (which can cause inaccuracy in shooting).
Have an iPhone? Check out all 200+ new features coming in iOS 13.