Need a Safety Cover, are the new Mesh as good as solid?

I am shopping for a safety cover to replace my old tarp cover for my 18x36 inground pool. I've read through a few posts on here that say that the mesh safety covers let too much light in and you end up with a green pool when you open in the spring. But, i'm wondering if anyone has any experience with any of the "newer" mesh covers that claim to block 99% or 100% sunlight. Like this SmartMesh from Merlin:
http://merlinindustries.com/SmartMesh.html

Or from loop-loc that says it has a denser weaves that "blocks virtually all sunlight":
http://merlinindustries.com/SmartMesh.html

The only reason I'm looking at the mesh covers is because they're supposed to be lighter, otherwise I'd just get a solid one. How heavy are the solid covers? Can they be lifted by one person?

I'm not sure your premises are valid. I've been using a mesh safety cover for years and this season was the first time I've ever had algae in the spring--and that's mainly due to 2 factors: The excessive amount of rain we had, and...my neglect of the pool until mid-May--I normally start the opening process in mid-April, so it had a month of warmer days with no chlorine.

If you live in a typical northern climate, where winter means snow and ice, you'll probably find the mesh easier--water doesn't pool on it, and it's much lighter to handle. When your water temp is below 50 degrees, you don't get algae growth, especially if you prepared your pool water for winter. You don't actually NEED a cover in the winter--it mainly keeps leaves, twigs, junk and small animals out of the pool. And, of course, prevents people from falling in the pool.