Do people use these, and if so are there any particular brands that people recommend?

You are required to wear them for racing.

On the bay freesailing, some do, some don't. I wear one.

You have to be careful if you wear a waist harness that the pfd (umm thats personal flotation device) doesn't get in the way of the hook. The kayak ones sit nice and high. I prefer the thin impact vest type. Some have a big zippered pocket back and front that you can put a bit of foam in for additional float or a sheet of lead for ballast. Mine is neoprene and even with nothing in it it provides bit of float and a bit of impact protection. Mine is an old style Airrush kiting vest. I saw the same thing with a "Liberty" badge on it in a magazine once. I doubt that you can get one of those anymore. Board Crazy has some similar vests but I suspect they only work with seat harnesses - not sure though.

Thanks Mineral, the Pryde will be top of my list.

Yes I have got my Halo off, and no brace at all now but wont be sailing for a while yet, I'm scheduled for physio late Jan, I'll post more then as there was a bit of interest about physio

Keep the laughs comin guys, this forum is a god send