Will this interfere with the trunk seal?

The spoiler mounts at the rear edge of the trunk lid where it won't compress or damage the weatherstrip seal. Check fitment against your specific trim level before final installation.

Does this stay stable at highway speeds?

Yes. The hard panel construction and factory mounting points are designed to handle typical highway driving without flexing or movement.

Will I need to drill holes or use adhesive?

The spoiler uses the factory trunk-lid mounting points — no drilling required. Exact fastening method depends on your vehicle's trim. Verify mounting hardware compatibility before assembly.