Following my initial post on wheel nut torque settings I am pleased to report the wheels have not fallen off and have been pleased with the truck. I had it in for a service recently at Nissan dealership and checked wheel nuts before I did a wheel rotation - surprisingly not part of the survice! All nuts without 'indicators' were overtight - maybe the rattle gun was only put on the accessible nuts. Following rotation all nuts set to 130Nm. Will keep a check over the coming weeks.
Torque wrenches - I have used a Norbar wrench since 1985 and recently purchased a 0 to 60 Nm unit and had my 'old' one re-calibrated. It was out by 10 to 15%. I agree wrenches should be re-set to zero after use to preserve spring rate.
The incorrect use of poorly set/calibrated rattle guns is an issue for all vehicle users - stretched threads, nuts difficult to remove and crushed alloy rims.
My advice is be vigilant, especially after someone else 'touches' your vehicle.