[hasperdi]

I second this recommendation.

HAG Capisco is not cheap, it is an investment (that will hopefully last for at least 10 years). It fixed my chronic neck pain using regular office chairs.

Before buying it, I suggest you go to a retail shop / showroom to try it.

[freeqaz]

They have a 90 day return policy and, if you live near a store (they have one in SF), you can return it to the store easily.

If you do try to return the chair, note that it's a PITA to disassemble.