This really depends on the location where you want to install the strobe siren. Ideally a strobe siren should be installed where it is visible and high enough from the ground that it’s not easily accessible.
The WS-280 is a mains powered unit and comes with a 12volt DC power adaptor and a 10 metre cable. It’s similar to a mobile charger and you don’t need an electrician to install it as long as you have a power point within range. You can also use an extension cable if required. There’s a rechargeable lithium battery backup that will provide up to 7 days standby power in case of a power outage.
The SPS-260 solar powered unit is a great option if there is no mains power close by however it must be installed in a location that gets some sunlight and it cannot be installed directly under an eave or in a shady spot. Also keep in mind that the sun changes pitch during different sessions. This unit comes with a rechargeable lithium battery and it will continue to operate for up to 45 days without any sunlight.
The WS-105 is an indoor mini strobe siren and plugs into a mains power point. There’s a rechargeable lithium battery backup that will provide up to 24 hours standby power in case of a power outage.
The G5W can have up to two hardwired Tophat Piezo sirens. A Piezo siren is a great addition to your alarm system because they produce an ear-piercing noise when the alarm is triggered.