A note you buzz on the mouthpiece will not be the same on the trumpet because you are adding more tubing length (the trumpet). Watch this allen vizzutti clinic where he does a segment on buzzing. [ame=http://www.youtube.com/watch?v=DIRWgYWnLOc&feature=related]YouTube - Allen Vizzutti Trumpet Clinic 2 of 4[/ame]

He is not an advocate of buzzing, but he is one of the few I am sure.