I started with a used Rev A, and then realized the hinge issue was not due to users, but design. At the time, Apple was not agnologing the issue, so I decided to get a new Rev B, just to be on the safe side. The Rev A has about 1/4" of play, but seemed solid overall. Now, are people seeing play develop in the Rev B hinges (maybe not failure, but just play)? The Dell XT I will be selling soon has been my main machine for about 8 months, and it was a referb. The funny thing is, the hinge on the Dell never loosened up at all, stuff as a board (and that was a convertible tablet, a unit you would expect to develop some type of issue since it only has one hinge).