The idea is great and the chimes are wonderful but the app is awkward to use compared to Apples Clock app. For example, when the alarm goes off, you have to: 1) wake the phone 2) swipe 3) enter your security code 4) press the "home" button. Only then does the alarm stop. By the time Ive done all this, the benefits of being woken up progressively are long gone.
JRManuel about Progressive Alarm Clock