Hi
We've used the flight socks for many years now especially as we do long hauls. They do work as I always get swelly ankles when sitting for a long time and as yet I've not had them since wearing the socks. We also find that our legs are less achy when we get off the flight.
I'm a bit of a fidget on planes and I reckon this has probably saved me as I'm always moving my legs, partly because I'm short and can never get comfy! It really annoys me when airlines don't fit leg rests and very dangerous as the seat cuts into the back of my thigh. Therefore I also carry an inflatable foot rest, which was fine until it developed a hole by the valve and kept deflating!
Therefore I now choose my airlines and routes wisely even if it means paying a bit more.
I know two people who developed DVT's through airline travel, fortunately they were lucky and discovered just in time.
Book an aisle seat and then you can have a wander around without disturbing anyone and drink plenty of water.
Put the socks on before the flight because they are flipping difficult to get on when squashed in those little seats, unless you are a yoga bunny!