Ohh no not again. This topic has been beaten to death and basically most guys are brand loyal. I have a 2002 chevy duramax allison and i love it. I pull a 33 powerplay on a steel triple axel and it handles it fine. I also have mine lifted with 35" tires.
Everyone has an opinion and basically when you compare all the big three diesels they are all very nice. I will say one thing the allison trans is hard to beat.