Dono, I did not even know they had a wab site. I think the build class 6 medium duty trucks that don't sell as well as they would like in the US. This would be like an F750, an Internaltional 4700 or GM's 6500 and 7500. Their larger engines are nice but not competitive with Cat, Cummins or Detroit (horsepower or torque).
Sorry if I took the thread in the wrong direction. My point was that Isuzu is not a major producer of Large diesel engines or large trucks and attributing some expertise to the GM engine offering based on that fact was incorrect.
baja bailey, good luck in your search for a truck, I don't think you can go wrong with either choice.