Are rubber hex dumbbells better than neoprene or cast iron?

Across the reviewers and home-gym communities we read, rubber-coated hex dumbbells are the consensus all-around choice: the hex heads resist rolling, the rubber protects floors and reduces noise, and the straight knurled handles feel closer to a barbell. Neoprene sets are popular for lighter, beginner-friendly weights but reviewers note the thicker grip can be uncomfortable above ~12 lb. Bare cast iron is cheapest but louder and harder on floors.