In terms of alarm type, there is no question now that photoelectric alarms are the best alarms to use in people’s homes. This is recommended by fire departments nationally and has been legislated in Queensland. In other words, you must install photoelectric alarms.
There are many brands on the market and many different price points.
It is important to choose smoke alarms that are tested and certified to the most recent Australian Standards. You can check this by looking for the Australian Standards symbol. Ensure it was certified under the most recent testing. Currently that is (AS) 3786-2014 so the label on the back of the alarm should state this.
Most hardware stores only stock alarms that comply with the current Australian Standards. If you want to be sure it is worthwhile sourcing your smoke alarms from a reputable electrical wholesaler. They tend to supply brands that are transparent about their testing protocol and provide quality guarantees.
Keep in mind QLD smoke alarm legislation requires properties to have interconnected smoke alarms located in hallways and bedrooms very soon.
It is a good idea to ensure the smoke alarms in your properties are models that can be easily interconnected. Some property layouts may even require wireless interconnection.
Plan ahead and know what system you ultimately need to install as it may save you money in the long run.