I just hope you have a good reason to have a siren. I know in my State, that would get you 6 months or more if used, Plus a hefty fine.
I think the reason you have had no reply's is that your on a thin line with those and there alot of LE's on here that are probabaly wondering the same thing as to why you have them.
I plan on getting one, just haven't set aside the funds to do so yet. In addition to what sk8deck stated, I'd be real careful when using that. If a local cop hears it and identifies you as the culprit, they'll be on you like white on rice.
I've got it, but I use my Av as a squad. If you purchased the remote siren kit I mounted 1 DPDT and 1 DPDT momentary in my center console as it puts it near the steering wheel area.