Some notes and feedback from people who have cycled to Paris on this route from 2011 onwards:

Piddinghoe to Paris by pedal power in July 2015 - Noel West and his partner Jane (not a bad place to live for this trip: Piddinhoe is just a hop and a skip from Newhaven)

This video from Adrienne Horne gives a splendid preview of the route, as does this account and videos from four riders from Oxted, Surrey to Paris in summer 2014.

Dominic Irvine gives an excellent account of the pleasures of this route done quickly or slowly

Alexander Morrice tells an entertaining tale of his trip to Paris with his mum, younger brother and college teddy bear.

Alastair Meikle gives a good account of what it feels like to do the route camping

George James and the Elmbridge Cycle group provided some very helpful additional notes on points of interest along the way:

http://www.elmbridgecycle.org/files/Paris-Day1.pdf

http://www.elmbridgecycle.org/files/Paris-Day2.pdf

http://www.elmbridgecycle.org/files/Paris-Day3.pdf

http://www.elmbridgecycle.org/files/Paris-Day4.pdf

George also wrote up their exciting experiences negotiating a group of 13 from Elmbridge to Paris, featuring an encounter with the sapeurs pompiers of Dieppe and wading through an ornamental fountain in Parc St Cloud to retrieve runaway instructions.

Sheila Bridge wrote an enthusiastic and entertaining blog about her adventures

Ben Lovejoy on his various adventures including struggles with loading GPS which may help others trying to do so.

Michael and Gina Cochrane blog about their various adventures and post some great photos of their London to Paris with some route variations

- An extended, more scenic route after Forges:

If you have more time, it is worth considering heading down the Epte valley cycle path, starting near Gisors, which is really beautiful and shows off the best of the Vexin region. For this, stay on the Avenue Verte until it ends in a track in the countryside beyond Forges, and head across country to near Gisors. 

One version of this is used on the official Avenue Verte from London to Paris. You can use this site to find your way. One option is to use the maps to link Forges and Menucourt on the approach to Paris, then to switch back to my route rather than doing the meanders of the Seine.

One rider, Colin Revel, has done this combined route, in the reverse (Paris-Dieppe) direction, having also done my full route, and says it's an interesting variation. His remarks from Vigny to Forges are here.

Here are some other people who have gone this sort of way:

• Alan Buttler took a route in this direction – I’ve also added a suggestion of how to extend his route further.
• Chris Smith gives some useful tips for cycling in this direction, along the Epte valley cycleway from Gisors to the Seine which he describes as particularly beautiful.
• Julian Radford gives some particlarly useful tips about a scenic and not too hilly way of joining the Epte valley with the continuation of my route in Triel