Butterfly - thanks for that I was concerned about the obligation aspect of JD.
Peli - that's very generous of you and both Mrs S and I appreciate the offer.
I think we will end up going down the JD route since I recall looking at the tandems on the trail and thinking that in the event of thermonuclear destruction of higher lifeforms at least the roaches would have some thing to ride.
We will probably go down the JD route, realistically I think this will be a spring thing since we are busy for the next few weeks and taking Mrs S out in a Yorkshire gale is not going to be conducive to the success of this project, but we'll see what the weather does at the end of the month.