I've spoken Mandarin Chinese for about 10 years now, and speak it fluently. I began my study with Speak Chinese Today. I always tell friends and students that one of the best ways to learn Chinese is by listening to dialogues on tape.
The essential part of Speak Chinese Today is the authentic dialogues perfomed by native speakers. Each of the dialogues is spoken at a natural speed, which is not too fast for beginners since the accompanying text includes each dialogue in Chinese characters, Roman characters (Pinyin), and English. The dialogues are rich with culturally-important information essential to learning not just the language, but the culture the language represents. These dialogues also help listeners learn the rhythm of the language, a very important element.
Even 10 years later, I sometimes recall parts of dialogues from Speak Chinese Today. For me, it has been and continues to be a catalog of useful phrases and vocabulary. Repeated listening allowed me to file away most of the wonderful dialogues in my mind. I highly recommend using this audiotape in conjunction with the book as the foundation of any elementary or intermediate spoken Chinese language course.