They work very well on short, well maintained lawns. If you have really thick, tall, or stalky grass and weeds then you may have a problem with them. They also require a lot of horsepower. I have a set of the new ones here and I had to take them off of my mower. Although they do come with a 30 day money back garantee I am going to hold on to them and try them out on leaves in the fall.