If all you want is a relaible, simple and effective alarm system to protect a building without the hassle of wires or a degrees in electronics to fit it, this one will do. Unlike others buyers it took me more than an hour to put it together, more like 2, but then due to past diy disasters I actually read the manual and watched the dvd several times before going at it for real! The only fly in the ointment was that somehow the tamper switch hadn't been bent into the correct shape (apparently a banana ;-)). However a quick call to one of Friedlands technicians, who by his manner I think had worked for NASA, had that sorted. Not one false alarm since install.