We had this doorway jumper for Calvin which, after hearing how other 
kids his age were enjoying theirs, we finally put up. We sort of figured that it would be an extensive installation, but in all actuality it was very simple. In fact, the hardest part about the assembly and installation was having to use a screwdriver to open the battery case. Battery case you might ask? For what? Well, they don't make jumpers like they used to. The one we had came with an activity tray and removeable electronic toy console (better known as a whatchamawhoozit) that made Calvin cry every time the music played when he spun the shiny wheel in the middle. This was an 
extremely unfortunate circumstance because Calvin's new love in life is spinning things (and someone in the commercial baby world knew that was coming because every toy we have has a spinny majiger on it). And aside from the fact that the toy made him cry, the jumper was basically useless. The tray set the whole seat off balance, the result of which was Calvin's obstinate refusal to do anything but lean back. And spin the spinny do-da. And cry. This was a major disappointment to both of us, Jon specifically, since he loved his own doorway jumper at that age (and remembers it so well, really).
The moral of this story? Sometimes less is more. After three days with this failure of a jumpy seat, we decided to exchange it for Johnny, the good ol' boy. You know, Johnny Jumpup? He may be wearing a new suit, a sage green one with bugs all over it, but he's still the most reliable old pal on the block. And it may look boring by comparison, but man is it fun! And it sure gets Calvin moving. We see a video in the future, possibly set to "I feel like dancing."