I got my replacement lens and the new Xpel protection. I have to be honest, when I saw $5 for a STICKER that was supposed to "protect" my lens from stones I was skeptical.
This is no ordinary sticker. The thing is as thick as the glass lens itself! The sticker feels tough as nails. I have a new confidence. I feel like this sticker might protect the bike during a motocross start!
I don't think the protection should be optional. Spring for the extra $5 if you buy these lights. It's cheaper than $10 for a replacement lens.