After reading a number of stories about people losing or nearly losing wheels due to improperly torqued lug nuts/bolts, I went around the car with the torque wrench. Everything was fine.
I do the wheel changeovers myself, as I've always done, so I was fairly confident they were ok. But then again. 
I've been in a vehicle to which this has happened.
When I was a teenager, my Dad wanted to spruce up his Dodge Ram with some new wheels and tires. He bought a set of new aluminum rims and a nice set of Michelin tires from a local Hamilton tire shop, who also mounted and installed them. The day after, he wanted to take a trip with his truck and new wheels, so we drove out to Port Dover for lunch. We made it to Port Dover, and were on our way back. It was raining. We were on Highway six, just south of Hagersville, doing the speed limit, when we felt a vibration coming from somewhere deep in the truck. It lasted for about 10 seconds, and we didn't think much of it, other than some sort of weird road condition. About a minute later, we felt the vibration again, and all of a sudden the rear driverside corner of the truck dropped to the ground. My Dad wrestled the truck to the shoulder, and as we pulled over, we saw a brand new wheel and tire come bounding and rolling past us, on down the road into the opposite lane. Luckily, there was no oncoming traffic, as that wheel and tire could have gone straight through a windshield and killed somebody. Instead, it rolled for a few hundred meters, before settling in the ditch on the opposite side of the road.
Upon closer inspection to the dropped axle, all the studs were bent, and some were even missing. This mean't that installing the spare tire was not an option. Luckily, my Dad had a cell phone through his work (this was 1998?!? - cell phones were not common place) and we were able to call for a tow. The tow truck came (a flatbed), loaded the truck, and drove us the hour back into the city. The driver dropped the truck off at the tire shop, before driving us back home.
The next morning, my Dad called the tire shop and talked to the owner, to explain why the truck was sitting in his parking lot, with a wheel in the bed. My Dad bet that the reason the wheel had come off, was that the mechanic had probably forgot to torque the lugnuts, and just left them finger tight, probably. The owner tried to argue this, and said that a thief had likely tried to steal the wheels at some point in the 24 hours from when the wheels/tires were installed to when one came off, but got spooked and left after only managing to loosen some lugnuts. Haha. Yeah Right.
In the end, he took partial responsibility, and ended up replacing the broken/missing studs, as well as replacing the wheel which had been damaged. He didn't end up paying for the tow, unfortunately, leaving my Dad on the hook for that part of it.
Lesson is: Always check the torque of your lugnuts after having wheels/tires switched over, as you never know if the installer was a numpty who effed up.
All I gotta say is, we were lucky the truck was empty when it happened, as opposed to when my Dad was towing his 29' Striper fishing boat (about 9000lbs), as it could have been much, much worse.
