A latecomer to Australia's crowded streaming music scene, Amazon Music Unlimited ensures that Alexa-powered Echo speakers are always ready to belt out your favourite tunes.

Amazon's all-you-can-eat music service offers a three-month free trial, after which you can pay only $4.99 per month if you just want to access it via a single Echo speaker. Alternatively an $11.99 p/m Individual plan works with multiple devices, but only one at a time.

Busy households can step up to the six-user $17.99 p/m Family plan, but Amazon doesn't offer a free Family trial so you'll need to pay from day one.

Amazon Music Unlimited is attractive if you own Echo smart speakers, although Amazon's speakers (unlike Apple's locked-down HomePod) also work with iHeartRadio, TuneIn and Spotify Premium in Australia, but not Spotify Free.

As you'd expect, Apple Music and Google Play Music don't work with an Amazon Echo speaker. Amazon is optimistically hoping Australians will buy its smart speakers and make the switch to Amazon Music Unlimited, rather than sticking with their current music service and buying a Google Home or Apple HomePod for their coffee table.

In terms of features, Amazon Music Unlimited stacks up well. It offers iOS and Android apps which let you stream or download music for listening offline, supporting AirPlay streaming to Apple-friendly audio gear but not Chromecast streaming to Google-friendly gear.

You'll also find desktop apps for Windows and MacOS, which don't offer offline playback but do let you access music stored on your computer, automatically finding your iTunes library.

Unlike in the US, Australians can't upload their own music files into Amazon Music Storage for streaming to their various devices. It's not a vendetta against Australians — Amazon is shutting down its Music Storage service around the world — although Google and Apple still offer this feature.

Rather than installing desktop software you can also listen to Amazon Music Unlimited via a desktop browser, streaming to Google speakers if you're using the Chrome browser. Finally, you'll find Amazon's music service built into home entertainment gear like Sonos wireless speakers, some Smart TVs, Amazon's Fire TV Stick Basic Edition streaming video dongle and of course Amazon Echo smart speakers.

Amazon offers a local catalogue of around 45 million tracks, roughly on par with its rivals, and can hold its own when it comes to Australian content including stations and playlists inspired by local artists. Searching for two dozen Aussie music acts from the last 50 years doesn't turn up any glaring omissions.

There are a few quirks when using Amazon's music service on Echo speakers which might frustrate you if you've spent time with their rivals. For starters the Alexa smart assistant isn't as good at interpreting your requests. Ask her to play "Joshua Tree", "LA Woman" or "Rolling Stones" and she doesn't pick what you'd expect, even though these albums and artists are in the library. Meanwhile Google Assistant and Siri know their music legends, although Siri on the HomePod is still prone to mishearing your musical requests.

The Echo speakers also leave surprisingly large gaps between tracks, particularly noticeable when listening to live albums. It's made more annoying by the fact tracks don't fade in and out, so the audio cuts out abruptly.

After Alexa has played your requests she falls silent, similar to Siri on the HomePod, whereas when Google Assistant runs out of music it automatically creates a Pandora-style station — influenced by the song or album that was playing and your taste in music — which can keep you entertained for hours.

All up Amazon Music Unlimited is a worthy contender but there's nothing here to tempt Aussies to defect unless you're buying Echo speakers.

We're slowly getting more pieces of the Amazon puzzle and the ecosystem will look more attractive when Amazon Prime shipping comes to Australia — especially if it bundles streaming music and video — but for now you might not see any reason to change your tune.