Here is the setup that I have.....
W "+forward"
A "+left"
S "+backward"
D "+right"
and...
SHIFT+W "autorun 1$$powexec_name Prestige Power Dash$$powexec_name Prestige Power Dash$$powexec_auto hasten"
SHIFT+S "powexec_name Prestige Power Dash$$powexec_abort$$autorun 0$$powexec_auto hasten"
What this does is it allows the normal WASD movement, but I only have to hit Shift-W to turn on autorun with sprint, and Shift-S to turn off the autorun with sprint. If I want to stop running but keep sprint on, I only have to hit "S" to stop my forward momentum. This lets me keep my right hand around the WASD for all my movement and keeps turning sprint on and off manageable. The added benefit to this bind is that it makes sure that I have my hasten on auto just about 100%. I sprint around enough to guarantee that hasten will be always autoed.