Chim-A-Lator, Lock-Top, and Lyemance Sealing Damper

Hello all,

Has anyone used one of these? I am encountering brands like Chim-A-Lator, Lock-Top, and Lyemance. Has anyone had any experience with these brands? I like the Chim-A-Lator and Lock-Top because each has the mesh around them to keep the critters out.

I'm looking for an easy way to seal the top of my 30' chimney in the spring and summer, and the above products look to be a good solution.

Thanks