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Abstract High-Frequency Torsional Oscillations (HFTO) present a major challenge when drilling hard formations, often leading to reduced performance and tool failure. This paper compares two modeling approaches for evaluating HFTO stability across the drilling system: a fast analytical criterion-based simulation and a detailed time-domain simulation using reduced-order modeling (ROM). Both aim to predict bit-induced HFTO excitation and rank bit designs accordingly. Both modeling approaches use a shared physics-based bit force model to compute torque response as a function of weight-on-bit (WOB), depth-of-cut (DOC), and RPM. The first method applies a damping-based criterion for rapid HFTO stability assessment. The second uses a physics-informed ROM to simulate dynamic responses over a wide range of operating conditions. Both incorporate BHA configuration via sub-models to generate torsional stability maps. Validation against lab and field data confirms their reliability and practical relevance. Experimental testing of ten 8½″ bit designs on a full-scale lab BHA showed that cutter and blade configurations can influence the HFTO-stable operating space by up to 40%. Both models successfully ranked bit designs while accounting for key BHA parameters such as motorization, damping tools, and inertia. The criterion-based model enables fast evaluation (under 5 minutes), making it suitable for early-stage design screening and real-time field use where speed is critical. It integrates well with automated drilling control systems to enhance rate of penetration and decision-making efficiency. In contrast, the ROM approach featuring axial-torsional coupling offers deeper insight into instability mechanisms and is best suited for thorough system validation prior to deployment, albeit with higher computational effort. This work introduces two complementary simulation frameworks that advance HFTO prediction and mitigation. The ability to rank bit designs without extensive experimental calibration marks a significant technical step forward, supporting more stable and efficient drilling operations in challenging environments.