Tempurpedic office chair?

[Mikmac09]

I am in need of a new computer chair and have been looking at the temperpedic models at staples since every cheap computer chair I've ever had goes flat and uncomfortable after just a couple months. I know the seat cushions are made from memory foam but does anything think it would be safe? I wouldn't buy a memory foam mattress due to the chemicals and off gassing but what about a small office chair? Do you think it's enough to be concerned over?