Check out the zebras. This is the best of both worlds. You can use them as a headlamp or just unclip it.
This... I've been running the same zebra light for the past several years. Bright, durable, and lasts a relatively long time. I simply unscrew the tail cap about 1/8 turn and the light cannot come on in your pack. If I lost it today I would have another one headed my way tomorrow.
Andy