UK Cam manufacturers are outsourcing cam blanks and particularly followers from China and India. In an engine that doesn't have a particularly great valvetrain design and will run a cam off in the blink of an eye, giving it any greater opportunity to do so, will be fatal for the cam.

Newman make their own stuff, but sadly that means going over to solid lifters. While this is a far better option for performance and eliminates the high-end missfires etc associated with 'other' manufactuers cam kits, it isn't an easy option to fit.