The Echo Dot is the most popular voice-controller speaker available from Amazon.
Pro's: 1. Improved sound and a new design compared to the 2nd generation. 2. You can manage your calendar, set alarms or timers, add things to your to-do lists, get weather and traffic updates just by talking to Alexa. 3. You can connect your own speakers over Bluetooth or via the 3.5 mm audio line out.
Con's: 1. Subscriptions may be required to use steam songs from Amazon Music, Apple Music, Spotify, TuneIn and others. 2. Most Alexa Skills are not available in Australia or have limited features - you're playing a waiting game for the developer to add support.