The mat arrived without packaging and was filthy - it had to be cleaned before putting down on the carpet in my office. Even though it is "heavy duty" it still dimples making chair movement a little difficult. Bottom line - it's just OK.
This mat has little spikes on the under side which keep it from sliding around when I move my chair. Unfortunately when I sit in one place for a while the chair creates dents in the mat; then when I try to move the chair rolls back into the dents! I'm not sure what I'll do about that.
Unpacked easily and fit perfectly. Very clear view of new flooring underneath it. Edges are very smooth and slide under pedestals readily. Thumbs up on all counts.