1. How do you pronounce the "Vita" of "Vita Sackville-West"? Uh, is it "VEE-tuh" or "VIE-tuh"? Who cares? Let's just tell the buyer how to pronounce "sackville" and "west", in case that's not obvious (?).
2. How do you pronounce the "Childe" of the painter "Childe Hassam"? Who cares? Might be like "child" or might be like "chilled" -- too much trouble for us to research it, and any idiot must know how it's pronounced, huh? So let's just show the "hassem"-sounding part, and let the buyer guess about the given name.
Even when only the surname is in question, they can get it wrong. Example,
3. How do you pronounce the last name of the artist Charles Demuth? M-W says de-MOOTH (rhymes with "the Truth"). But the Demuth Foundation tells me "The Demuth family appears to have pronounced their last name de-MOOTH (similar to the German). Charles Demuth appears to have taken some artistic liberties with that pronounciation. The artist pronounced his last name DEE-muth after about 1915." In other words, let's ignore the way he pronounced his name during his prolific years from age 32 to his death at 52, and show the pronunciation he used before he had his first solo exhibit in 1914.
Buyer beware. If you go by this book's pronunciations (or lack thereof), you might look as dumb as it does.
It's not surprising that in such comprehensive and informative book (it has circa 30,000 entries!) there are some mistakes (e.g. wrongly spelled first and even last names like in the cases of Viet Stoss - correctly spelled first name is Veit - and B. J. Feijoo y Montenogro - correctly spelled last name is Feijoo y Montenegro), and overlooked important persons (e.g. famous Welsh novelist and playwright Richard Llewellyn, who died in 1983, doesn't have an entry!)
However, it's still definitely one of the most authoritative biographical dictionaries available (it's simply the best, just like its twin brother Merriam Webster's Geographical Dictionary is in its field - see my review there!), and is worth every single penny or cent. I use it pretty often and hardly wait for a new edition with new entries and, of course, some necessary corrections (some of them contributed by me).
A note on the choice of entries. A biographical dictionary does not contain living entries. For that sort of information you need a Who's Who type of publication that has constant updates. It is usually a very expensive purchase, and the buyer has to be meticulous to be certain he is getting the "type" of persons in which he is interested. In this day and age of 15-minute celebrity, to include everyone anyone has ever heard of would take a constantly shifting entire library.
