Sigma 24-70mm f/2.8 ART lens has its strengths and weaknesses. Pros: - Image quality: Excellent in the center, especially when stopped down to f/5.6. - Build quality: Rugged and weather-resistant. - Video capabilities: Good for video, with minimal focus breathing. - Filter threads: Uses the same 82mm threads as other popular lenses. Cons: - Autofocus: Not reliable for professional action shooting, especially when tracking moving subjects. - Resolution: Can be poor away from the center, especially at f/2.8 and f/4. - Distortion and vignetting: Moderate barrel distortion and light fall-off in the corners, which can be corrected by stopping down. Overall, the Sigma 24-70mm f/2.8 ART lens is a good choice for general use and landscape photography, but may not be suitable for demanding professional applications where high reliability and sharpness across the entire frame are crucial.