Centerforce or Spec Clutch?

I've always been a Centerforce fan but everyone in the mustang world seems to be crazy about SPEC clutches. Is there really a diff? Also anyone know about what it costs to have one installed? I dont have any place to work on my car to do it myself and I'm going to be taking a large road trip im just over a month. Currently the clutch seems to grab ok, but it seems like if I dont MASH the clutch to the floor it grinds a little when shifting up or down. :mad:
 
My 02 just got 40000+ miles on it. I do lot's of drag racing so I know My clutch are bad . It slips and even I did adjust my clutch it didn't help. Now my tob whistle so I need I need to change it fast.
 
The TOB whistle isnt bad as long as it doesnt do that when the clutch is engaged.

I am going to buy Spec when I upgrade simply because many people do give rave reviews for them for quality and having a good TOB that doesnt squeak.

Based on what you are going to do to your car, decide on what stage clutch.

Mild boltons: Stage 1 or 2
Any kind of FI go with stage 3.....