As mentioned in the description, this mattress did take a full 48hrs to come up to the 8" level. I also did a bit of walking on top of the mattress on both the days to aid the process of getting it to its full shape. On the day of unpacking, there was a mild odor but on the second day, there was nothing. 

If you are from India and used to "firm" mattress, this mattress is more on the "medium to medium firm" level. So keep a note of that. Used this for the last couple of days and no complaints from my wife and myself.