Which is the best quick reference?
Looking over the two, which would you use for information referenced on the Model T, they both say the same basic information on dating of a T, but one is more detailed than the other. Which would you go to for quick information for your vehicle?
#2 by far, IMO.
Depends on what information you're after. For mechanical procedures, you want the Ford Service Manual. For history, correct parts, etc., Mark is right. The second you show is very extensive. There is a version on disk that is even better because it includes a lot of material that isn't in the paper version. I call it the best $50 you can spend on your Model T.
The first one is a fun get your feet wet book, but No 2 by far. I like my printed copy.