It is great to have everything you need. If nothing else, it saves time and aggravation. It is also nice to find out what doesn't work in a non-emergency too.

Regarding the bus, I am kind of uncomfortable wearing ear buds (mp3 player/radio I assume) on public transportation or in public in general. I find that they hinder my situational awareness.

Then again, I am just an old fuddy dud...