Will this diffuser scrape on steep inclines or driveways?

The diffuser adds minimal extension below the stock bumper line. Approach angle depends on your suspension setup and driveway slope. Inspect ground clearance on your specific vehicle before finalizing installation.

Is this purely cosmetic or does it provide functional downforce?

Circuit-style diffusers are designed primarily for aesthetic impact and visual aggression. Functional aerodynamic benefit is minimal at street speeds and depends heavily on overall bumper design and air flow. Install it for the styling.

What prep work is required before painting?

Sand and prep the surface with appropriate grit before applying your chosen color. For specific surface prep steps and primer recommendations, reference automotive finishing guides or consult your paint supplier—they'll ensure adhesion matches your topcoat system.