I have a question about the airlift.  It seems that when someone who is average to lightweight sits on it, it holds its position, but when someone who is heavier sits on it, it moves down an inch or so.  Is this normal?  All the stools do this and we ordered four of them.[...]  The stools seemed fine, however.  Please let me know about the airlift movement and if this is normal.Otherwise, we love the look of the stools and they fit in beautifully with our bar area.