Replacing a Simon XT panel with external strobe and siren?

I’m done with Brinks and need a new panel or module before 3G shuts down. What do I need to have the Qolsys IQ Panel 4 work with a external siren/strobe? And also just want to make sure that the Qolsys IQ Panel 4 will work with all of my Simon Xt sensors, window, motion and smoke that I already have currently.

What do I need to have the Qolsys IQ Panel 4 work with a external siren/strobe?

This depends on the intention. Are you referring to a new wireless siren or an existing wired siren?

The IQ Panel 4 does not have wired siren terminal. Wireless sirens are compatible, like the PG9901, PG9911, and the Z-wave QZ2300-840

And also just want to make sure that the Qolsys IQ Panel 4 will work with all of my Simon Xt sensors, window, motion and smoke that I already have currently.

The standard 319.5 Mhz version of the panel would be compatible with GE319.5 Mhz sensors used on the Simon XT. Note that if you have Alarm.com Image Sensors those wouldn’t be compatible.

Also always check the expiration date on smoke detectors. While they may be compatible, if they are beyond the replace by date then it should be replaced.

Thanks for all the info.
I have an already existing hardwired siren/strobe
ATW Security Doberman Indoor/Outdoor Siren & Strobe Combination -Blue Low Voltage Security
that is hooked up to my Simon XT panel and if possible I’d like to keep it.
Would using a IQ Hardwire 16-F or IQ Hardwire PowerG work with my current siren/strobe?

Thanks for the tip on smoke detectors, I’ll check out my existing ones expiration dates.

The IQ Hardwire 16F and the PowerG Hardwire translator support triggering wired sirens, but if you do not have any wired zones it is a rather elaborate work-around and I would recommend just replacing the siren with a PowerG or Z-wave model.

For outdoor use I highly recommend the wireless PG Outdoor siren