Re: Fr.
We done it last year not by choice on the return journey because of strike and we are going to do it again at Christmas because of the cancellation of the route Ireland/France by Irish ferries in December and to be honest I prefer the direct route. Via landbridge uk, the connection between the ferries are usually not very suitable you always end up spending a lot of time waiting for your ferry, in addition to the cost of the ferry don't forget to add the cost of the petrol and it is not cheap in the UK, it is a very tiring journey and if you have small children it is very long for them. My choice will be the direct route as it is stree free and if you wish you can sleep during all the journey, better to be on a boat (if the crossing is not too bad) than spending in a car which children asking every 5 minutes are we there yet ???.
The saving you are making is very small if any and to small for being rewarding