I think how effective the vest is, is a very subjective thing. A lot is dependant on how compliant you are. My daughter is 5 & 1/2 and when she got her vest a bit more than a year ago it was like heaven!!!! she would sit and watch her shows or a video and it was fine (as long as we padded the area where her g-tube is) but now she knows how to turn it off and on, and can really turn on the tears about having to get it done. She says that it makes her itchy or that it upsets her stomach. At first she brought up a large quantity of mucus (much more than with manual PT, postural drainage or excercise) every time she used it even though she was NOT sick, but now she is really clear and only occasionally brings anything up. I do thinjk that the vest helps her to stay really clear. I know many just hate the vest and won't do it or they don't use it for long enough or at the prescribed frequency or pressure. so I guess that for me as a parent, it is great. CPT is being done effectivelyand my tendonitis is not aggrivated. For Rachel, though, she doesn't want to be tethered to that machine for that whole time and all that shaking sometimes makes her itchy and uncomfortable. she would much rather jump on the mini trampoline everyday instead (but she never wants to do that long enough either)So my opinion is this. If you are going to be compliant it is great and definately worth it!( but how would you know unless you tried it first and felt it?)Andrea