It is hilly, but not steep or technical just longish climbs typical of the South Downs really. I would say it will be along the same kind of lines as the rides that we've been on with Mike before.
Andyz I remember you being fairly speedy (I think did you have an Overburys?) so I would think you'd be fine on a 30 lb bike, I've not been on the best form lately so I wouldn't think you'd be the slowest by any means.
Godders a SS would certainly be doable although I think it would be hard work on some of the climbs. I suppose it depends on how much you ride it? I think you'll be fine but if you're worried bring the trusty Cannondale.