It's not my choice but what was here when I bought the house. My sewing room is in the basement divided into 2 main rooms. One side has this indoor/outdoor carpet glued to the concrete so its not coming off easy if I do chose to remove it. The other side is concrete but very uneven concrete. I should have had them level it especially where my quilt frame sits but of course hindsight. We also found out the floor in that section slanted downward at one end to almost 3 inch difference. Another thing we didn't realize until I had them add another doorway at that far end. That's when it was noticeable. Had to hike up the quilt frame quite a bit on that end to make it level. If I had my choice, I'd just go with all concrete as it's easier to clean, vacuum and so forth. I have a rubber mat in front of my quilt frame to stand on to make it easier on my feet and back.