Drums and beaters are able to spin up far quicker simply because they have a lower moment of intertia (essentially more of the mass is closer to the center of rotation than a comparible weighted disc). This has advantages and disadvantages. Advantage is that it spins up quicker however you have to spin it to a higher speed to get the same kinetic energy as a comparible weighted disc.

Spinning at such a high RPM will be an interesting experiment certainly but you will have to be careful that bearings etc are rated for such speeds and whilst it won't be an issue for you Dave, the machining has to be top notch as any misalignment or friction in the system will cause a spectacular premature failure.