Buyers should prioritize the engine type, typically a liquid-cooled, 4-stroke, single-cylinder engine for the 250cc class to ensure a balance of power and fuel efficiency. Key performance metrics include a power output of approximately 20-22 kW and torque around 24-25 Nm. Additionally, verify the presence of Bosch EFI (Electronic Fuel Injection) for reliable starting and WP Apex suspension or high-quality equivalents to ensure superior handling. For safety, ensure the braking system features Brembo or ByBre four-piston radial fixed calipers with dual-channel ABS as a standard requirement.