I have had mixed results with this product over the years and can offer two bits of important information when using Shoe Goo:

1. Absolutely make sure to clean the intended surface as much as possible before applying. This will not adhere well to a dirty surface.
2. Don't expect miracles. This does well on smaller holes and cracks, but I have have not had any luck with larger shoe repairs, such a large cracks across the width of a sole.

A good product as long as you follow the directions closely, and have appropriate expectations.