Is The Sigma 28-70mm F2.8 DG DN Contemporary Too Cheap?

Sigma is a company that makes some questionable choices. We'll never discount their image quality. But the rest of the package is just always odd. Take the new Sigma 28-70mm F2.8 DG DN Contemporary. For the most part, they say it's an Art series lens. But the big differences are with the build quality and the focal range. In fact, the Sigma 24-70mm f2.8 DG DN Art is around double the weight. For what it's worth, we also really liked that lens and gave it a five-star review. But the Sigma 28-70mm...