The Sony Baby Call Nursery Monitor has worked fine for us.  My son is now four and we still use it.  It has two different settings.  One, you can hear every single thing going on in the room and two is the voice activated setting.  I prefer the first one.  The first one allows you to hear some things you will definitely miss if its on voice activation.  One time we were able to hear my son getting sick so we could get in quick to get him to the bathroom and avoid a huge mess.  Another time we were able to hear my son talking and laughing hysterical in his sleep.  On voice activation you...