The problem with some GM cars, which I believe has been addressed in newer models, is that elemental sulphur sometimes crops up in gasoline as a contaminent, which isn't a big deal from what I understand. But it plays haywire with the fuel tank sensor in some GM cars, especially Cavalier and Sunfire apparently.
I have an older Achieva, which doesn't get driven much, and it has run out of gas before on me when the needle is at a quarter tank or half tank. I rarely drive the damn thing: my son who normally drives mentioned it happened to him a couple of times so he always treats it as it's almost on empty when the needle approaches the halfway point.
The problem gas could crop up from any gas station.
GM says it doesn't happen much.
I'm going on sketchy memory: TO Star had a big piece on it on Dec. 22, noted a couple of incidents when people ran out of gas while on the 401 or 400, can be scary and downright dangerous when you're doing 100 k and all of a sudden the car dies.