Well generally I like the chair. After about 1.5 years the mesh is still okay - no rips. Unfortunately the nylon base developed a crack and now the gas piston is literally dragging on the floor. Replacements under warranty are on-order but won't come for probably 2-3 months so I'll probably have to try to buy replacement parts (assuming I can get this thing taken apart) even though it's still under warranty.
The mesh seat is tearing where it's attached to the frame on the side after 8 months of use. I'm 165 pounds I didn't expect to have to replace this within 1 year.
I was having daily back pain and trouble standing up after sitting for 2-3 hours at a time for work. I put this new FlexFit chair in my office and within 2 days my back pain went away and noticed a huge difference and total reduction of back and neck pain.