I just found out that there are, in fact, seven different producers of Roquefort. From Wikipedia:
"As of 2009, there are seven Roquefort producers. The largest by far is Roquefort Société made by the Société des Caves de Roquefort (a subsidiary of Lactalis), which holds several caves and opens its facilities to tourists, and accounts for around 60% of all production. Roquefort Papillon is also a well-known brand. The five other producers, each holding only one cave, are Carles, Gabriel Coulet, Fromageries occitanes, Vernières and Le Vieux Berger."
I've only ever had the Societe brand and I haven't stumbled upon any other variety yet.
Has anybody tried more than one brand, and if so, is there any difference?