I use The Master Genealogist and my sources can be rated from 0 to 3 within my database. A source rated "3" means that the information is the best that I can obtain to prove that fact. I have almost all of my "facts" documented, although some are still not proven. But I do have documented where I obtained the information that I am using as the clue to find the fact.
Along with the Whitney line, my other major colonial line is Parker. These two families shared alot of common space over the years. There are many others, but those are my major colonial lines. With the Parker line I can trace direct ancestry to John Alden and Priscilla Mullins so technically that is my oldest colonial line.