It's been a little less than 2 months now, but I've noticed a difference of about 105cc on both sides. The one with less filling is very soft and feels like a bouncy ball when you lie down and touch it, but when you sit on it, it's soft, but the one with a lot of filling is still very bouncy. After seeing a few posts saying that they regret the feel of the Motiva, I regret going with Menek.