I have used 24hr time since I was around 7 or 8 years old. I find it much more comforting but then again I dislike ambiguity. I do however feel odd when having to translate things to someone who asks for the time. My wife is especially annoyed by my use of 24hr time. She doesn't like that the hour field goes past 12 on all my clocks or my use of European date format with the day ahead of the month and my frequent use of standardised date format really irks her with the year before the day before the month. She also doesn't like to use any of my calculators since they're RPN instead of algebraic... then there are my keyboards which have all had their caps and left-ctrl swapped (as per ANSI/VT100)... I could go on.