When selecting a BLDC motor controller, you must prioritize Voltage Range (V) and Current Rating (A) to ensure they match your motor's peak and continuous requirements. Key technical factors include the Control Algorithm (e.g., FOC - Field Oriented Control for smoothness, or Trapezoidal for cost-efficiency), Feedback Mechanism (Sensored via Hall Effect sensors or Sensorless for high-speed applications), and Communication Protocols such as CAN bus, RS485, or PWM. Additionally, verify the MOSFET quality and Heat Dissipation capabilities to prevent thermal runaway during high-load operations.