...I use Power Service about every third fill-up, mainly because of people on this forum suggesting it. But also, I have a couple of friends locally that have gotten bad fuel with water in it, and the Power Service claims to remove the water (I guess it has alcohol in it). Its cheap and also seems to have taken care of the rare billow of smoke I see in my rearview when I punch it at night.
Another thing I noticed is that a lot of people only will buy diesel at truck stops, and other specific locations. Then there are others that burn SVO, WVO, Kerosene.......To me, one of the neat things about a diesel is the universal nature of the fuel. I figure I can put crap in it if I condition the crap properly