I have not tried them myself, but, yeeeears ago, I used to work for a car rental agency. We used to have a guy come out once a week and fix all of our chips/bullseyes, and cracks. He was even able to fix a 15 inch crack once. I never had to call him back to re-do a repair.
I would see what a Professional charges, and have him do it. The main reason is that they will usually give you some sort of warranty.

-Larry

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D