My son, who is almost 16, has had the Vest for four years. He uses it for 20-30 minutes in the morning and gets his Pulmozyme dose during that time. In the evening, though, we usually do standard percussion (CPT). If we're away from home, Jordan uses the Acapella, which works much like the Flutter, but is easier to use correctly, according to our cf doctor.
Jordan has mixed feelings about the Vest. It makes him cough more, and he's not convinced that it's a useful cough. My impression is that the Vest and CPT act somewhat differently and that the combination works better than either alone. For whatever it's worth, the lower-airway score from Jordan's PFTs began rising within a month of the time he started using the Vest and has continued to rise until reaching the normal range for a kid of his size. That may be a coincidence, since he started to run a lot and to take Biaxin (similar to Zithromax) on a maintenance basis at about the same time, but I suspect that all three changes contributed to the improvement.
The Vest is expensive, and even after it's paid for, you don't own it. Advanced Respiratory, the company that makes it, offers the equipment only as a "lifetime lease". This is not all bad, since any repairs or adjustments are made by the company for free (as a child grows, he or she will need to be refitted). In addition, the company has had a policy of never requiring a patient who has been provided with a Vest to return the equipment, even if insurance doesn't end up paying. You may be asked to contribute something toward the balance, but if that is a hardship for you, the company will not insist.
Hope this helps.
Bambi, Jordan's mom