Buyers must prioritize spindle speed (RPM) and torque based on the material being processed; for example, high-speed spindles (12,000+ RPM) are ideal for aluminum, while high-torque spindles are necessary for steel. Additionally, evaluate the positioning accuracy (±0.005mm or better) and repeatability, the number of axes (3-axis, 4-axis, or 5-axis), and the Automatic Tool Changer (ATC) capacity. Ensure the machine uses a reputable CNC control system such as Fanuc, Siemens, or Mitsubishi for better software compatibility and operator familiarity.