First off, this package got to me in two whole days and I was so pleased. It's boxed small enough to lift easily, is not heavy or cumbersome and was well packaged. Upon opening it, there was no chemical odor, which is unusual for memory foam toppers. I bought an XL twin for my side of our Cal King, because my husband likes a super firm mattress and that's just not comfy for me. This is 2 inches thick, so our made bed looks odd, but I figured that would happen. The foam isn't heavy, and though the instructions said to open and ventilate for 48 hours, I did not, and there was no problem. It was as comfy last night as it was the first night I opened it. The foam is dense, and very comfortable. I would definitely recommend purchasing this as the price was outstanding.