"Octavarium" peaked in the top five in the Finnish, Italian, and Swedish charts, and in the top ten in the Dutch, Japanese, and Norwegian charts. Critical reception of the album was generally positive; the diversity of the music was praised, although critics found some of the songwriting to be inconsistent. Dream Theater promoted the album on a year-long world tour, with the majority of concerts lasting almost three hours and featuring a different setlist each night. The tour finished at Radio City Music Hall accompanied by an orchestra; this performance was recorded and released as a live album and concert video entitled "Score". They co-headlined the 2005 North American "Gigantour" with Megadeth.