If you go in early Sept the fall folage in Utah, Idaho, W Wyoming and Montana equals anything you will see in the NE states with less crowds and traffic. I've done both and I wasn't impressed with following the bus tours and paying higher prices for quaint (rustic) motel rooms, nor eating alot of fish, not my favorite, although the maple syrup was keen. Besides the driving experience in RI and Mass is something I never want to do again. We were following a major hurricane from NY making the circle back through the New England states so the weather was crappy, flooding in Cooperstown and trees down everywhere. Rain, rain and overcast skies. Bad experience, but not unlike living in Oregon.