One thing to be aware of with this cruise line -- the passengers were mostly age 65+, with only a handful of people not yet retired (we are in our late 50'3), and almost no one under age 40. Having said that, the passengers are generally a very well traveled bunch, and we enjoyed the discussion at meals. People also were very good at getting back to the tour bus on time (best we have ever seen on a cruise).
Pluses: The informality of the check-in and check-out process, friendliness of the crew, hosted cocktail hours every night, free cookies, snacks, coffee, soda all day, and an absolutely terrific port lecturer (Laurence).
Minuses: Only one key to the stateroom; food was very average the first few days, although it improved over the course of the cruise; small bathroom; cruise was pricey; several crew members were brand new and "learning the ropes". Some tours were not so great & didn't allow enough time at stops (i.e., Mt St. Helens)
This was our second cruise on American Cruise Lines (the first being the New England Islands in 2010), and we have already signed up for the Charleston to Jacksonville cruise next year. If you enjoy smaller ships (~100 passengers), older well traveled passengers, convenient access to ports, and the informality of a smaller cruise line (vs the often frustrating experiences aboard the large ship cruise lines), you should consider these cruises. They are also adding Alaska and Mississippi river cruises next year.