My 1999 E300 Turbo diesel is

1. My second MB

2. My first diesel

3. My first turbo vehicle

The question: I have heard that one should let the car idle for a minute or two to let the turbo cool down. I have also heard that the turbo spins at about 100,000 RPM. Are these statements accurate? Should cool down be done everey time it is driven and what are the implications of not allowing the turbo to cool down?