I think Tralenta is near Bonneville-sur-Arc, if its the same place you are looking at. There's some nice photos in the Petzl catalogue, and some topos plus a video of some meet there on the freestone website;
http://www.freestone.fr Looks like a really nice spot, and maybe a bit cooler as its at fairly high altitude. Dont know about Tarantaise though. Give us some feedback if you get there, I am probably in the area thi summer.
