The Jouef TGV Duplex comes in three train packs should one wish to model the full length train. HJ2013 contains a power car, dummy car and one first and one second coach. HJ4017/8 between them have six more coaches: one bar car, two first class and three second class coaches. Incidently the Hornby International catalogue shows them offering the TGV Sud-Est, P.O.S. and the 600 world record unit also.
The reason for a double-decker TGV was popularity. In particular the Paris-Lyon-Marseilles route where double heading of TGVs has been necessary. They seat 545 passengers which is 45% more than other TGVs. The TGV family, besides what's already been mentioned, includes Atlantique, Reseau, Thalys and Eurostar.
The model itself is very impressive as the following photo shows posing on a segment of my club's layout:
The power car has a centrally located motor in a metal chassis with fly-wheels driving all four axles. It's nice and weighty and can haul the full set easily. It has all-wheel pick-up and one traction tyre on each bogie off-set. The twin pantographs are very fine and by removing a piece of adjacent roof one can turn a screw for overhead pick-up. Twin head and tail lights work in the direction of travel. It's DCC ready but I am still a ludite
I can't really comment on this aspect. The power cars are connected to the coaches by a coupling that looks a bit like a close coupler. Mine didn't quite line up but I was able to reposition them to between the bogie underframe rather than under. The coaches share a bogie (I can't think of the term!) and clip together best by holding them in a "vee" and sliding in. You do this as there's a locating pin to ensure they don't come apart. The effect with the connector covering the gap is pleasing. Any niggles? On the dummy the pick-up wires were too tight and causing considerable drag. Try as I might I couldn't seem to ease them so I sent them back to Hornby [our Australian distributor doesn't do Jouef but does Lima and Rivarossi 
] and they sent it back with no cost to me except the original post so I like many others can't fault Hornby's service. My verdict? Well it has a 'wow' factor at my club and runs very well. Aside from the niggles I mentioned it's going to be one of those models that gets alot of running time. Verdict? 9/10.Here are some thumbnails for you to look at:
