We are experts on this, as most everyone knows who followed this board in the past!!! The mechanical sofa in the 2400, with the air mattress was AWFUL! I won't go into all the details, but I'm sure you have the same complaints. In short, the good folks at Phoenix changed the air bed completely with an electric, memory foam sofa bed that was easier to open and much more comfortable!!! I believe they are now installing only the electrics with memory foam. There is a charge for the replacement, since it does involve a pretty full days labor, but in my opinion well worth it.
We have since traded the 2400 for a 2350, with memory foam & electric, and are very happy "campers"
Jack