$129 may sound like a lot of money to spend on a pencil, until you use the 2nd generation Apple Pencil. After using it for a day or two, I'm confident you'll find it to be worth every penny. If, for any reason, you are not satisfied, Apple will give you a full refund within 14 days of your purchase.
An Apple Pencil can scratch the surface of your iPad, but only if the tip of the pencil has embedded foreign debris and that embedded debris is pressed into the surface of the iPad. To prevent your Apple Pencil from scratching the surface of your iPad, simply inspect the tip of your Apple Pencil before each use.