Any Outdoor Alarm Siren that works?

What is an alarm system any good if you can’t give alarm to the outside/nightboors? I am trying to find an easy to setup outdoor sirene that works with the MiCasaVerde controller - any sugestions?

I use two Fortrezz ssa2. One in the garage one on patio. Aside from one unit that died quickly, they have been reliable so far (9 months or so).