The first one is stunning! Great colors! I'm not quite sure about the contrast/composition of second one..maybe a slight crop and contrast boost would improve it?
The last image is my favourite, and i've got a feelin' it'd look great toned also.
Dungeness is quite a sensitive site, how much freedom do you have to roam around at will in this area?
I live in Essex and have thought about takin' a trip down here myself.