They work but could be better.
Your review: Adjusts from 27" - 36" high. Acceptably sturdy if braced against a wall. Steel is 2mm or 0.08" thickness.
Pros: Only 24" deep legs that were available across numerous websites.
Cons: Box construstion makes it difficult to use power tools to tighten fasteners. Only a single hole in each leg for fastening to floor. Shelf stiffener blocks access for attaching to floor w/ concrete screws. Lack of access adds extra time to installation.