When sourcing a Coordinate Boring Machine (CBM), the most critical factor is positioning accuracy and repeatability, typically required within the 0.002mm to 0.005mm range for high-precision tooling. You must evaluate the spindle run-out, table load capacity, and the X/Y/Z axis travel limits to ensure they meet your specific workpiece dimensions. Additionally, look for machines featuring thermal compensation systems to maintain accuracy during long production cycles and hydrostatic or high-precision linear guideways for smooth, vibration-free movement.