All dealer up sells for the most part are a huge waste of money, huge markup and usually either something you can get elsewhere for much less or just an insurance policy covering damages which depending on where you are and your habits may or may not be worth it - for me I am careful with the car and rarely have any issues, so over the years it would have been much cheaper to repair anything out of pocket.
It is pretty much just a sealant that you can do yourself for 20 bucks and then an insurance policy to go with it. The company that sells it, sells it to all car dealers that they can get to resell it - just for comparison, Ford will sell you the Protector for $299 on a new car - BMW just marks it up more because people are willing to pay more!
2008 335i Vert Montego/Saddle/Grey Poplar
2014 X3 35i Space Grey/Chestnut/Fineline Wave