There are so many pedals on the market and its frustrating to find a pedal that is right for you, But my recomendment is pearls new demoon drive pedal, dw's 9000 series pedal or tama's iron cobra pedal. All pedals mentioned are $$$ but the quality is outstanding, and the speed you can get from them is great. I was from a drummer mate that a good place to find out what pedals are good and all things metal and double bass drumming is t go to a myspace page. www.myspace.com/doublebassdrumanswers
have a look ad see what you think let me know.
All the best