From most of the posts above the advice seems to assume that the unfortunate aircraft will ditch in the English Channel or the Irish sea.
My opinions voiced above are not limmited to the waters near the UK and are what I would do if I was about to ditch away from the UK in an area that is not as well covered with SAR assets, with the airliners all monitering 121.5 these days if you are about to ditch in the Southern Med the first responce that get to a "Mayday call" is likely to be from an airliner.
This leads me to think that most of you don't venture much south of Le Touquet................ there is a whole world of great flying to be had if you go south....... go do it !!