I'm planning on riding some of our nation's "rail to trail" routes beginning next year. The majority of these seem to have crushed rock surfaces, the Katy Trail in Missouri being archetypical, though some are asphalt. Some are day rides, and many are treks of several days from start to end point. I anticipate carrying no more than rear panniers and a bar bag; essentially "credit card" touring plus. I'm trying to identify the best bicycle for this sort of activity, and I'm gravitating toward the Trek DS or the Giant Roam series. Any thoughts or suggestions, especially based on personal experience?