Fan clutch choice

Would you recommend the standard or the heavy duty clutch for that? Tampa Bay heat.. then I'm also looking for performance gains, then some people have told me it seems like the heavy duty clutch Never disengages fast enough...
The HD unit will not slip a much as the standard.
So the HD will provide more air.
I have had several clutch fans when your driving you cant tell when the fan engages or disengages. That sounds like interweb bullshit.
Keep in mind the clutch never locks up 1:1 even when they are fully engaged they still slip a lot.