http://www.autogeek.net/wg5500.html

Would it work on gel?

In theory it would but may not last very long. Most automotive paint sealer do not contain suitable abrasives to clean or prepare a gel coat surface as it is laying down the polymer coating. What it means is that the bond between the sealant and the surface may not be optimal to get the best bond and therefore poor durability from the product.

I make a product called Big Kahuna Polymer Sealant which contains unique micro abrasives designed for gel coated surfaces. It enhances gloss and provides a durable finish.

Feel free to check out www.hulaboatcare.com for more info