Dragon Ball Z's third film, "The Tree of Might", has had a long history in terms of English dubs. The first dub, produced by FUNimation, split the movie into three television episodes of DBZ. These episodes were distributed by Saban and featured the Canadian Ocean voices. A year later after Saban ditched the show, FUNi and Ocean redid things with Pioneer and the outcome was a more accurate uncut dub. Two other (bad) English dubs were subsequently made in France and Malaysia, before FUNi finally redubbed the film in 2006 with the current American cast.
The main reason i prefer this version is because of it's musical score. The "Shuki Levy score" (which was supposedly composed by Ron Wasserman) is far more suspenseful and exciting than any other DBZ soundtrack. Shunsuke Kikuchi's original Japanese soundtrack for this film has way too much silence, which gives the film a very mundane feel, and the music itself is boring and unfitting. Nathan M. Johnson's electro-orchestral score from the 2006 redub was just totally forgettable.
The script used isn't perfect (quite a few cringy one liners) but the awesome Ocean cast make up for it. Ian James Corlett in particular did much better here as Goku than Peter Kelamis or Sean Schemmel.
You can find this dub on FUNimation's 2013 "Rock the Dragon Edition" set, where it's packaged as a full-length movie instead of three individual episodes.
