I bought this Jun 3 and the assembly went well and looks great.  Soon I noticed that the lid seemed to be "warping" or rising up on both ends.  I recalled an earlier reviewer who wrote about that.  Upon inspection, I determined that the pneumatic tubes (called gas tubes or something in the manual) are both defective.  One locked up completely after it was extended and popped off eventually and the other returns only 80% or so to the closed position.  It is not the plastic warping.  I called customer service today, a Saturday, and two new tubes are being shipped in two weeks.  So far, good recovery service.  I write to help others who may think their lid is warped.