James Dewar did the vocals on B.O.S. but really some of Trower's best work is in Procol Harum. The albums A Salty Dog,Home and Broken Barricades are some of the best rock of that era. I saw Procol Harum at the Santa Monica Civic on the Broken Barricades tour and Trowers solo on Whaling Stories ripped the roof off that sucker that night. Whaling Stories is my favorite guitar work by Trower,he was in the zone that night.