I went from an Ikea Markus to a Maxnomic one. The Ikea one lasted me less than two years before the cushioning had just gone, but this was from sitting in it for hours everyday, other people may have different experiences. I was however in Ikea recently and they have changed the colours and things so maybe the padding is improved now also, or I just got a bad one.
I have only had the Maxnomic one for a few weeks, but I like it, no idea on how long the padding will hold up in in but i do find it comfortable, it is a more pleasurable experience than the Ikea one. Though whether that is worth twice the price to you or not is another matter. The reason I went for the Maxnomic one over other brands is that I usually have my chair extended rather tall and out of what I looked at they went the tallest.