I live in a home with a lot of trees, and have wasted my money on several different expensive gutter guards. How do I know that Leaf Solution will work?

Here is what the manufacturer say:

Leaf Solution has been manufactured since 2002. Since that time, we have sold millions upon millions of feet. Still, after over 6 years, we still are an Accredited business with the Better Business Bureau with an A+ rating. The simple fact is Leaf Solution is the most effective gutter cover on the planet. It will take large volumes of water, yet prevent anything as small as a piece of sand from entering. We also back our product with a simple guarantee. If your gutters are ever to clog when protected by Leaf Solution gutter guards 5″ and 6″, we will refund your purchase price.