Interesting, though as you noted it's less than 1/1000th the size of the 530B model and according to the article is only used in about one in ten U.S.-based Eng

Interesting, though as you noted it's less than 1/1000th the size of the 530B model and according to the article is only used in about one in ten U.S.-based English-language searches, at least when that was written.