How do 'Dynamic Balance' requirements in high-speed turbines affect the choice of retaining ring?

Standard stamped circlips have large 'ears' or 'lugs' that create a significant mass imbalance in high-speed rotating assemblies (e.g., turbochargers). Spiral retaining rings are 'dynamically balanced' by design because they have a uniform cross-section and the ends are offset, resulting in a nearly perfectly symmetrical mass distribution. For extreme precision, 'balanced' spiral rings are manufactured with a small amount of material removed from the side opposite the gap to perfectly offset the mass of the ends. Using a non-balanced ring in a 50,000+ RPM application would induce harmonic vibrations that lead to bearing failure and shaft whip.