Just wondering if anyone has used these? They are quite expensive to buy so I didn't want to make a rash decision. My dd is 2 1/2 and is doing brilliantly with potty training (have cracked it in 1 week, including going out) but I am worried about night time and don't expect her to hold herself as she is a deep sleeper. So I am not worried about her wearing a nappy at night. Just wondering what others thoughts are?