Fast typing as well as all the fine arts require proper practice. I think that if you practice on a specific keyboard you will going to excel in speed typing especially in this very keyboard.
This law is called "The Law of Specificity" and applies on every side of human performance (sports, art etc).
*** It would be nice (as long as scientific) to search all the world records or Top-100 performances in touch typing and try to find out what kind of keyboards were used. If it proves statistically significant after then we can say for sure that there are some specific keyboards for the speed work.
Till then, let's find the keyboard that suits us better and practice, practice, practice!