Since the back shell is see through (Did any of you w/o one yet know that?). It'd be nice to have an LED light up in there when the button is pressed. I suspect my battery just died a moment ago, with nary a whimper to warn me. I'm away from a charge cable etc. at the moment, so I can't confirm, but it'd be nice to be able to take it off, flip it over and see if the power is truly gone.

Mine came with a metal back plus a clear plastic back.

Actually what would be nice would be a vibrate if power drops below a certain percent.

Mine only came with the transparent one. Is it possible to get the metal back?

Yup, there was small issue with a few of the metallic silver units going out without replacement metal backs. Please email me at [email protected] and I'll mail you a metal back asap.