Broke
I´d agree with that but after using the valve for 30 miles and it just simply broke, thats plain stupid.
We all agree with your situation,hell even Manley would agree that it sucks.
Manley or anybody that manufactures parts for aftermarket has no control over who assembles them,tunes the car,the fuel in the car,the driver etc.
Thats why when i build a engine for race purposes i don't spec anything,i tell them what i need (hp,torque,compression etc) & let them spec the parts,purchase the parts,run the engine on the dyno for 30 min-1 hour with me present,putting the engine through all phases of its limits,then have them install the engine in the car & chassis dyno the tune etc.
Then i pay the balance owing,knowing that it has been done & is operational to my requests.
If i go down the road 20 miles & it blows up,knowing it was working fine on the dyno thats what can happen & those are the risks you & i are willing to take in the name of performance.
Man i do feel for you as i know what those heads are worth.
Keep us posted!