In French, on their map demo which centers the map in Paris, it's already pretty bad. I honestly have no idea what some of the words mean.

Edit: A few examples taken randomly of mostly unused words in French (require a dictionary for a good 90% of native speakers): Volute, redise, dépiler, rapière, ânier, putatif, toison. All of that is in the center of Paris, and it took me 5 mins to find them, there's probably hundreds of rare words.