Either or considering your application.
I'm running a slightly modified 97 turbo car..,and the Viggen clutch seems to be more than enough. Got mine from Nick T...., over 2 years ago.
You can find them from various providers...SAS, Group 9, SAAB performance (http://fastsaab.itgo.com/
)...there are quite a few providers out there.
That paddle clutch is supposed to be really stiff, and generally used on applications exceeding 300hp. Which I'd really like to see an N/A do some day.