Based on the shared answers, the main differences are autofocus drive, coating, and a small weight change. The Mark II version appears to use its own internal focus motor rather than relying on the camera’s screwdriver-style AF drive, and it’s reported to be a bit lighter. It also has updated lens coatings.

In image quality terms, the lens is described as sharp and producing attractive results, so the optical performance seems broadly well-regarded. One practical note from a Nikon D5100 user: autofocus behavior in Live View may be limited or not supported as expected, so compatibility can depend on your camera body and how it handles AF with that lens.

So if you’re choosing between them, the biggest real-world consideration is autofocus compatibility and behavior with your specific camera, with coating and slight weight savings being secondary differences.