I did the night rating soon after completing my PPL and it sharpened me up no end. I would recommend any student to do as much instrument training as possible.
A very wise person pointed out to me to just check to see if the horizon is actually coming towards you and as long as you are only ever flying to the horizon with appropriate speed and height you will never go inadverdant IMC. (Not sure about night though)
DMCD is at Denham. Fast used to have one at Thruxton too. BRRY(I think)
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Use it don't abuse it.
What day is it anyway?