This is nothing more than a repackaging of Busby Berkeley volumes 1 and 2 released in 2006 and 2008, respectively. There is a bonus disc of just the Berkeley musical numbers included, which brings us to 10 discs, so I don't think the 11 disc description is accurate. I rate this a four because the first collection was definitely a five, but the second collection is more like a three with Berkeley's lesser and later films included. The following is a listing of the individual films included and the extras on each disc, just in case you don't own either of the original Berkeley collections:
42nd Street: 3 featurettes ("Harry Warren: America's Foremost Composer," "Hollywood Newsreel," "A Trip Through a Hollywood Studio"); notes on Busby Berkeley
Dames: 4 featurettes ("And She Learned About Dames," "Busby Berkeley's Kaleidoscopic Eyes," "Good Morning," "Eve and Melody Master: Don Redman and His Orchestra"); 2 classic cartoons; Direct from Hollywood radio promo; theatrical trailer
Footlight Parade: 3 featurettes ("Footlight Parade: Music for the Decades," "Rambling 'Round Radio Row #8," "Vaudeville Reel #1"); 2 classic cartoons; theatrical trailer
Gold Diggers in Paris: the Broadway Brevities musical short The Candid Kid; 2 classic cartoons
Gold Diggers of 1933: 5 featurettes ("42nd Street: From Book to Stage to Screen," "The 42nd Street Special," "Gold Diggers: FDR's New Deal... Broadway Bound," "Rambling 'Round Radio Row #2," "Seasoned Greetings"); 3 classic cartoons; trailer gallery
Gold Diggers of 1935: 2 featurettes ("(buz'be bur'kle) n. A Study in Style," "Double Exposure"); 2 classic cartoons; Direct from Hollywood radio promo; trailer gallery
Gold Diggers of 1937: the historical short The Romance of Louisiana; 2 classic cartoons; 2 excerpts from 1929's Gold Diggers of Broadway
Hollywood Hotel: the historical short The Romance of Robert Burns; the Edgar Bergen/Charlie McCarthy comedy short Double Talk; classic cartoon
Varsity Show: Edgar Bergen/Charlie McCarthy comedy short A Neckin' Party; classic cartoon