I have the Twin Carbon, but I recommend the Twin HD cerametallic for most. I only have the Carbon, because Exedy gave it to me to test. I've driven it daily for a few months and done 5 drag launches at an auto-x, but that's nowhere near the abuse it will get starting in mid-March when the NASA season begins and the drag strips open...

 

How does a weak clutch put strain on the tranny?