Thu, January 10, 2008 (6:15pm EST)
Oricon's most recent sales figures show that Kobukuro's "ALL SINGLES BEST" has sold more than 2.71 million copies since its September 2006 release. This makes it the best selling album by a vocal duo, surpassing CHAGE and ASKA's 1992 collection "Super Best II," which sold a little less than 2.70 million.
Source:
Oriconhttp://www.oricon.co.jp/news/rankmusic/51088/full/