I've now finished all 1-30 units of Phase 1, in anticipation of a vacation to Italy, and am very impressed with the program. It's not your standard memorization / grammatical structure drills like we had in school. It teaches you conversationally, in a very organic way, that seems to assimilate and stick better. I think the conversational emphasis gives you a more natural accent too. Highly recommended.
My wife and I, along with another couple, used this audiobook to tour Rome, and we also used the same series in Florence. We found it very informative and a great way to see sights we never would have seen on a mass tour. It provides interesting information and a little exercise after the Italian cooking. I highly recommend it.