Ditto here. I've thought about getting cell service for the alarm system. It would be a little more per month and a one-time charge to convert, but it might be cheaper in the long run. Then the landline callers could go pound sand.
I get a lot of calls (and a few texts) on my cell, but I don't answer any number I don't recognize, and they never leave a message. I'm sure that wouldn't be practicable for a bidness cell, but mine ain't, so it is. heh