The last time I tried one of these it entirely failed to find anything for my route - plus as I say usually I think these rely on cheap advance tickets and you're at risk if your first train is delayed of no longer having a valid ticket for the second half of your journey.

But to be honest I'm *much* less interested in the fact that faffing with tickets can sometimes save you money and much *more* interested in the the fact that the simple ticket was simply unavailable - costing me money in practice. I've had no sign of an acknowledgement or reply yet.