Hi Mimi's Mum,
I first used a Respisense about 21 months ago when my oldest son was born. I used it for about 10 months, and thought it was fantastic. I am now using one with my second little boy, who was born last Saturday, so it obviously has my vote!
One of the big things we found, was to make sure that it was placed correctly on the nappy, otherwise it wouldn't sense movement properly and we had a couple of false alarms. But we figured that was better than some of the stories we had heard from friends about their Angelcare - if the washing machine or the fan was on, then it wouldn't alarm, even if their baby was in the cot and the monitor on!
I would highly recommend that you get a Respisense.