Had a failure, but let me explain. It was a cheapie where you pay about $50 for a year or more of service (the owner was wanting to avoid a monthly bill and since the site had broadband in place, this met his goal). The problem it had is that it did not pass the DTMF tones...If you called into the line and answered the phone, you'd hear perhaps the 50 milliseconds of the first tone then no more tones would pass. At that point, the RFC1/B was dropped and a Broadcast Tools Site Sentinel 16 was installed directly into the broadband router. The only downside to that box is that it can not place phone calls. If you can live with emails and texts for your alarms and logging in via the web for your metering and control, it's a winner.