Steve_Cox wrote: * Smoother operation. A belt's teeth completely engage into the system for decreased friction and increased pedalling efficiency.
I realize this is from Wiki, but that one is particularly hard to believe.
Smoother operation? Yes, rubber will no doubt damp out vibration unlike the somewhat rattly chain. But everything I know about mechanics tells me that efficiency is lost compared to chains.
Complete tooth engagement means more friction. When adjusting backlash between gears, minimum friction occurs when the teeth engage just enough to prevent skipping.
Motorbikes do use belt drive these days, but a cyclist applies power quite differently to an engine. The fact that your feet 'pulse' power means a somewhat stretch feel as you pedal.
In a motorbike RPM is quite high so the belt can 'float' a bit on the pulley's which reduces friction markedly. As you slow you may find you notice the extra friction. No cyclist will be going fast enough to achieve this float.
As far as the rust issue, OK, but a drop of oil per week and neither will a chain. It's no fun riding in the rain anyway. Rubber on the other hand will perish in the sun. A good belt will have armid fibre (a bit like kelvar) reinforcement, so might cost a bit to replace.
Just some thoughts.