Bests & Worsts Reviews from Amazon

The product definitely cuts down on light coming in the sides of blinds. But, not nearly as effectively as they could, and at far too high a price for what you get. Here are some issues (and how to fix them): 1. The magnetic strip that sticks to the wall -- some people say it comes off. I just put mine up, so I haven't experienced that yet, but sounds like a problem. 2. In the real world, walls aren't perfectly flat. The product makes no accomodation for this. What happens is that the magnetic strip that sticks to the wall conforms to the wall's surface, you then (also magnetically) attached the L-shaped part to the magnetic strip on the wall. But, the L part isn't nearly as flexible as the magnetic strip on the wall. So, it doesn't conform where the wall isn't perfectly straight -- gaps are left between the two magnetic strips. These gaps let light in, and they reduce the holding strength of the already-weak magnets. 3. The black paint/dye that is used to absorb light is glossy. So, when you look at is straight on, it looks black and so looks like it would do a good job of absorbing light. But, when light hits it at an angle, the light glares off the surface -- it's like a black mirror reflecting light into your room. 4. On top of all this, what you get for $60-$80 + shipping, is two L channel extrusions, and four magnetic strips (one on the wall, one on the L part, for two L parts). The L channels cost $5 each (e.g., see jifram.com/stock-plastic-extrusions/l-channels/). So that's $10 in materials. The magnetic tape costs less than $15 per set of two L parts if you buy a 100' roll (Amazon sells it -- search for "Self Adhesive Flexible Magnetic Tape"). So, they are selling $20 of materials (and that's a retail -- if you were buying in bulk obviously the cost would be lower) for $60-$80. Which I wouldn't actually have a problem with -- you are paying for the convenience of not figuring it out for yourself -- if the product worked great. It doesn't. So, if you are willing to do a tiny bit of work, here's a cheaper, better way to do this: Buy the plastic L extrusion. Buy enough self-adhesive velcro that you have 2X the total length of the L parts. One length of the self-adhesive velcro gets stuck to the L part, one part gets stuck to the wall. Why? Because the velcro offers a little bit of thickness to help with gaps if your wall isn't perfectly straight -- use the magnetic tape though if you want. The other velcro isn't being used as velcro at all. It's just being used as a bumpy black surface, which is really good at absorbing light. So, rather than paint the insides of the L parts black, stick one side of the velcro to each, and voila! You now have a black surface that doesn't reflect glare. (The velcro tape should be about as wide as the L parts you choose). Now you have a better product at half the cost. And, you don't have to paint anything, drill anything, or anything else messy or difficult. The only thing you have to do that you don't do with the this product is apply self-adhesive velcro to both inside faces of the L parts, to make them have a great light-absorbing surface.