I don't want to overlook some of the other good pastel products that come out of France.
Have a look at Pastels Girault, whose sole focus is pastels. Unfortunately, I have only tried a few of them, so I can't give a critique.
Additionally, there is the legendary Henri Roche pastel line. The story line for decades has been: "Good luck trying to get a hold of any of these beauties". You had to hire a private eye, or a French-speaking guide to help you find the secret location of their lab in Paris. Then, if you had a bottomless wallet, you actually found the shop, and you also have found it to be open (only Thursday afternoons), you may then be privileged to purchase a handful of these goodies for yourself.
The apparent key is the pigment to binder ratio. I will say no more.
Now, we are blessed to have a distributer in the US: Fine Art Store of Rochester, NY.
I don't have any, myself, but I do accept both bribes and gifts...
If you enjoy funny stories, don't miss Barry Katz' search for the legendary pastels, here.