Ive had my ACT HD-G6 sprung hub six puck for 2 years (25000 miles) and it still holding strong. Ive have never once experienced the lock out that some complain about. Mine easily shifts past redline, 8K + shifts. For me its been a great clutch for the money.

 

I wish I could shift at 7800 rpms with my ACT The stupid thing locks me out of gears if I try to shift above like 7300 rpms. It holds my Red on pump gas just fine, and is great on the street, but at the track it makes me want to rip out my hair.

 

street disc = lock out

sprung 6-puck = no lock out.