For fun, I hooked up a Simplex QuickAlert (4903-9419) and a TrueAlert (4906-9127) in series on a 4006 panel (blue board c. 2020). I found that both signals do sync with each other. The TrueAlert has a slight delay on the 1st pulse, which I’ve noticed with the newer SmartSync TrueAlerts.
You love mounting pull stations into panel cabinets don’t you?
If it works, it works.