The Iver Johnson doubles have one peculiarity that may take a little getting used to. The top lever doesn't latch in the open position like most doubles, and is cammed open when closing the gun. I guess there is nothing wrong with this, it's just different. The guns seem to be well made and durable.
I have never owned an IJ double but have several guns which have this feature, including British, Continental & an early side pivot Lefever. Personally I much prefer it to the "Lever Latch", but that's just my opinion. All my Lefevers except for that one have the central pivot levers & do have the lever latch. They are among my favorite guns, but in spite of rather than because of the lever latch.