Zip06,you've got some good answers from the guys.Owen,thanks for that link,I like that 12 inch chisle.
I am a pry bar fan myself,to me in a city it is the "urban fixed blade".For a blend of the 2 check out Beckers Tac Tool

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Yes the bigger the better,but... the harder to carry.That Pry Baby is cool and would save a lot of broken knife tips if evertone caried that along with their folder.
But don't sell a smaller bar "short",its like the .38 snub in your pocket beating the .45 at home.I carry a 7 inch Stanly flat bar,5 bucks and I got to say wow,how did I get by without it.Your not going to tear doors off,but I have slid the latch back a number of times to get though locked doors,popped some windows,and if nothing else it may open up enough of a gap to stick something larger in.
Heres a recent story.A couple months ago we catch a highrise fire,its a Saturday so not many people at work in the building.The fire knocks out the electric system and back feeds the emergency generator,so no almarms or back up lights go off.People don't know theres a fire,till some smell it others when they see/hear the firetrucks pull up...
So they try to leave,go out into the stairways like they should,only the stairways are pitchblack and have some smoke entering them...some are afraid to go down and can't go back into their office 'cause the stairway doors are locked from the stairway side.
We had people laying on the stairway floor sucking air off the ground,to scared to go down unable to go back in their office floor.
I used that little bar to open more than one door to check floors for people.If they had one or that little Pry Baby on them or even in an office "go bag" they would not have been laying on a dark, dirty stairway floor that is filling with smoke.