I did use filter socks for about two months. They trapped a lot of detritus and worked well as mechanical filtration. I stopped using them after installing an egg crate shelf and layering it with floss. I found the filter socks to be cumbersome to use on my system and dreaded getting to them in order to clean and change them. Not good in terms of maintaining good tank husbandry habits. At the moment I am happier with floss, my phosphates and nitrates are zero, and changing the floss is much easier than changing the socks.
One day, as need arises I may go back to socks because they are effective. Just right now I am happier without them.