The mattress inflated as soon as I cut the plastic. My 3 year old son, very soon after laying on it, started hugging it and saying he loves it. If you don't like a soft mattress, this would not be the mattress for you; however in spite of it being so soft, it offer a good level of support. I didn't find myself sinking into it when I layed on it as some others experienced. I also expected an odor and there was none. The quality of the mattress surprised me and this is more than the temporary mattress fix I was seeking. I am very pleased with this purchase and my son is over the moon, making it easier to get him to bed at night.