I spent a total of 4 years with VW and BMW and from my experience the same people repeatedly blew their turbos, whilst others just kept on going. Sure, we had the odd dud that would pop after 3,000km but on the whole I think it's a lack of mechanical sympathy that leads to failed turbos.
Even though most would tell you its no longer necessary, I would still advise people to idle their cars for a minute or two before switching off. And don't nail the throttle before everything's reached normal operating temperature. You're dealing with tremendous kinetic energy when the insides of a turbo are spinning at 100,000+ rpm - let the poor thing catch its breath before you cut the air/oil supply...
EDIT
And lucky you, being at sea-level. The issues of get exasperated in the Highveld's thin air...