How many of you use turbo timers on your scoobs?

I have just got my first Scoob, 1999 STI 5 Type R, and have seen a few posts in the past about leaving your car running for a min or two when you pull up. Do you only need to do this when the car is not going to be used for a few hours (it will cool down) or do you need to leave it running every time you stop even if it's for a few mins.... e.g. getting petrol etc???

Excuse my ignorance but I was just curious, as I don't really want to replace my turbo any time soon!

If any one has comments on the above or using Turbos Timers, make/model etc, they would be appreciated.