Should always re checheck the torque of the wheel after few hundred miles, or sooner if you like. I use a "click" type torque wrench and there have been times where I have found that few a hundred mile later the heels need retorquing.
As far as the pointer type not needing calibration, you are right, however those wrenches rely on sping tension, which over time will wear. You then have to buy a new wrench all together.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member