That's exactly what I've been using, but it's just not quite warm enough over the 200 miles. Hands, body, head, feet are all sorted with the kit I have; I just need to get the leg department sorted. Am taking a look at the ideas offered up here and have some good clues. A lot of the suggestions here are for waterproof overtrousers but of the unlined variety, so they solve the keeping dry issue but not the getting cold one.
I should add that I am particularly averse to getting cold but I can take all the heat that can be thrown at me.