I'm off the belief that you can't have enough smoke detectors. I noticed a thread where someone (thankfully) woke up to smoke in their rig. The smoke detectors finally did their job, but a little late. Apparently the fire started in the belly of the rig where converter is located. One of the items on my must have list for the new rig is a detector in the electrical area of the rig behind the wall in the storage area. I'll put it where I can check it through the round plastic cover. A fire could get going pretty good in that area before the detectors in the living area were to alert you. Not to mention your sleeping over this area and as we all know fire burns up and the wiring along with the wood framing is going to create some pretty bad smoke in a hurry.