We bought Leaf Filter for our house. Best investment ever. I don't even think about clogged gutters and/or downspouts anymore. They aren't cheap, but in this case, you truly do get what you pay for. The mesh of the cover DOES let water in, but no debris at all. I have known SEVERAL people who bought the cheaper systems with the larger holes. Those holes are big enough for a leaf stem to get stuck. After a few leaf stems get stuck, other leaves get stuck behind it. Next thing you know, you have a pile of leaves stopping the water from going into the gutter, and the water overflows onto the ground. DO NOT question this. The guy behind me had those cheap ones put on, and the leaves built up on top of the gutter covers, and the water was overflowing onto the ground up against his foundation, and his sump pump was overwhelmed, and he got water in his finished basement. I had to bite my tongue to keep from telling I told you. I had recommended Leaf filter to him.
And forget about Leaf Guard. The premise of Leaf Guard is that the water will flow over the lip and back into the gutter (see attached picture). During a gentle or moderate rain that will probably work, but when it is raining cats and dogs, the water will be 'shooting' down the roof, and it will shoot right past the edge of that lip and right onto the ground.
Bottom line is that Leaf filter is the best. You get what you pay for. Leaf Guard will not work as advertised in a downpour, and the holes in the cheap ones will allow debris to enter the gutter and leaf stems to get stuck.
Your choice.
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