In your case it should not overheat. And it really gets no hotter in turbo than any other compact light that drives the XR-E decently hard in max mode. High is another good choice though, it looks pretty close but with much longer run time.
Thanks. Yes, the turbo does not seem twice as bright, more like 50%, but maybe that's psychological.
This evening I went for a 1 hour run in air that was close to freezing - 0 Celcius - and set the torch to turbo mode. At the end I checked the batteries and the head, and they were not even warm. So either they have modified the torch (lower turbo mode, better heat sinking) or the heat build up is localised around the LED with poor heat transfer, or the cold air was sufficient to keep the unit cool. I tried it for 10 minutes indoors, and again there was no heat build up, so I suspect they have modified the unit.
According to some they have added polarity protection in recent units, but the manual still warns against inserting batteries back to front.