Ok,
here is my review of the SC1200 unit. i got mine last week and set it up over the weekend. (in my part of the world this was a long weekend so I had lots of time). I believe that for the most part this one is a great improvement over the 7000.
First, the power sirens (both old and new) do work if they are on the same housecode (do not have to be on the unit code) BUT there is about a 15 -20 second delay before they start. If they are on the same housecode they will work as they would when triggered from any device on their code.
Second, it does turn on only 2 unit codes when the alarm is triggered and they cycle on and off at about 3 second intervals. Personally I have no problem with this as now I can specifically set up a macro in Activehome Pro for only the units I want on during an alarm. (Having the furnace room lit proves nothing).
Third, (this I really like) when you activate the alarm the housecode comes on to let you know that it has been armed. I have one housecode set to my front porchlight and when we use the remote from the driveway we get a flash to acknowledge our triggering of the alarm.
The type of activation varies with how you set the alarm. If you do it from a keychain remote you get a 1 second flash. If you arm it from the home button on the console you also get a 1 second flash. If you arm it for away from the console you get a 60 second countdown to allow you to exit before it arms itself.
The range is at least as good as the 7000 since I was able to put it in place and had no trouble with any of my existing sensors.
I hope this helps,
Wayne