With No Alarm, No Adrenaline Rush - Breathing Space Blog
If you have trouble arising at a time you prefer, experiment with going to bed earlier to find that time in which you can comfortably arise without an alarm clock.
A benefit, to knowing that you've gotten enough sleep for the night because you've been able to arise on your own, is not to awake in an adrenaline rush. "Alarm" clocks and other devices are named as such because they are meant to alarm you. Is that the way you want to start each day? Being jolted out of your reverie and thrown into waking consciousness ready or not? How much different would your day be if you woke peacefully, naturally, completely on your own?