This is one of my local tube stations so I use it very frequently to get in and out of town.
The first thing you should know is that the display on the platform that indicates when the next train will arrive is always being changed in the mornings. What I mean is that if it says 1 minute for a bank train and 3 minutes for a charing x train, and you decide to wait they will often change it at the last minute.
Usually if it says 1 minute it is unlikely to change but any thing else is subject to a destination change and this is always happening. If you are in a hurry, get on the first available train and change at Camden Town.
This is otherwise a nice and always very clean station. They have toilets on the platform which is unusual for the underground. The men's is on the Barnet platform and the woman's is on the London platform (you can simply walk across if you need to go).
The ticket office is not always open but you can usually find an attendant wondering around. read more