My 15 year old son has had the vest since he was 4. It has never really caused him to cough up anything even though his CT scans show lots of mucus in his airways. Recently, while hospitalized, he tried the IPV machine. Right away he began coughing up stuff. My doctor then ordered a machine for him, but my insurance refused to pay for it because they already bought the vest (11 years ago!). Do any of you use this machine? I know it may be considered outdated. Does anyone have an old one that they don't use and would be willing to sell? Any ideas on how I could get financial assistance to buy one of these machines?