I have this one too (obviously yet to use it though!). We have the sensor pads in her cot in her room, but she'll be in our room for the first 6 months so we'll use it without the pads til she's in her own room.

It was recommended to me by a friend who had one go off on her daughter - she's not sure if it was a false alarm or if her daughter actually stopped breathing, but she raced into the room immediately. She said it gave her great peace of mind