Per Brian Nystrom:
One thing I can say for certain is that having latex socks that I could
wear wool socks under was a godsend. Before I installed them, even much
short immersion was very painful on the feet. A friend of mine did a
test and spent 19 minutes in 28/29 degree salt water.

I wear NRS' "expedition-weight" neoprene socks under them and
Tevas "Neutron" surf shoes over them.

19 minutes is at the long end of what I can spend in 30-ish water
before I start *really* feeling the chill.

That's all well and good.... and 19 minutes is better than
five.... but it definitely puts things in perspective for me.
--
PeteCresswell