I read all the negative reviews and bought it anyway. I let it open for 48 hours. Yes, its a little taller in the middle than the sides, but not enough to make a difference. I think it will even out. The mattress edges are not as firm as a traditional mattress, true, but so what Its not a traditional mattress. Its to sleep on, not to sit on while tying my shoes. Its soft and plush and cool. Best sleep ever!