The double frame and 2 speed rear ends are little clues that this truck was built originally as a dump truck and not converted later. I've used both, and it's little details that you would not give much thought to that make a truck originally designed and built to be a dump truck much better to use. The 2 speed rears are really nice when you need that super low gearing, like backing up a really steep hill, etc. As far as the automatic/manual debate goes, do yourself a favor and learn to drive a manual. Even the automated manuals have limitations that make them less desirable for dump truck usage.