Just wanted to know if anyone is using these or had used them.
What do you think of them?
Great rail, very solid, rails where you need them, and smooth where you don’t.
I’ll echo Stick’s comments…
I like mine very much, 100% solid and easy to remove if you need to to.
I like my CASV-M. The only complaint I have is the two screws on the side that help hold the bottom piece on. They’re phillips head screws instead of hex. It’s a small issue, but I’m not about to sell mine and I wouldn’t prevent me from buying another one.
I’d love it if they made a rifle length version.
I just installed the “M” model on my new Mid-length I just recently completed building. I like it so much that I promptly ordered a second one for my next build within the next month or so. Super strong. No problem finding mounts for Aimpoint T-1 that allow lower 1/3 co-witness. You may not have the same results with the EOTAC at this time. 
How do you get your FDE casv rails to look shiny? CLP? All of the ones I’ve seen in person are neither shin nor smooth. They feel gritty and look really flat matte.
They are, its a matter of angles and lighting.