We maintain an absolute skeptical attitude. In addition to regular visual inspections, we focus on checking for sediment accumulation around the sunroof drainage channels and look for water stains under the A-pillar trim and front floor mats. This is the only effective physical evidence to determine if the sunroof drainage holes are blocked, leading to hidden leaks.

Basic perception functions (like Adaptive Cruise Control ACC, Lane Keeping Assist LKA, and Automatic Emergency Braking AEB) rely on the vehicle's local radar and cameras, and can operate normally overseas. However, advanced features that heavily depend on high-precision maps and cloud data (like Navigation on Autopilot NOA and Full Self-Driving FSD) cannot be activated overseas.

Experience turbo lag and power surge during road tests; check for significant oil accumulation at the turbo intake and intercooler connections (slight oil vapor is normal); and use OBD to read the real-time boost pressure peak to see if it meets factory settings.