We received the topper and I took it out of the box right away. It was sealed up in plastic, and getting it out of that was the hardest part. Once it was out, I spread it out for about 4 hours. I didn't experience any kind of lasting smell that others have complained about and I'm fairly sensitive to smells. It didn't reach full expansion, but the instructions say it will do that better if you sleep on it so I wasn't concerned and we used it that night. Both my husband and I snored significantly less, almost not at all. He loves how it feels on his back. We have the king and it covers just fine from edge to edge. The only downside is having to refit the fitted sheet every day or two on the tall side of the wedge, but that's kind of an occupational hazard of adding 6" to the mattress. I'm sure there are sheets out there that would fit better, I just don't have them yet.