Haha, I´m a native speaker from Chile. We pronouce it "burdeo" (http://thepocket.cl/2013/03/burdeo-el-color-del-2013/), without the "s", I never knew it was actually burdeoS, haha.
Also, with naranja and anaranjado, its actually accepted both ways, depends on the region. Sorry for my english and thanks!
Also, with naranja and anaranjado, its actually accepted both ways, depends on the region. Sorry for my english and thanks!