I expect this question is going to get a lot of the same responses as "What is your favourite equipment?".
Basically, I'm asking what you think is the right level of power for knights of have. Some stuff is called OP, some is called UP, so which gear is fine where it is? If you were to point at one sword, gun, bomb, shield and piece of armour, which ones would be measuring stick after which all other gear should be judged?
I've got my own ideas, but I'll wait with it so that I can get opinions on the matter rather than opinions about my opinions.
The ban stick.
http://wiki.spiralknights.com/The_Ban_Stick
It is a stick. Perfectly fine to use as a measuring stick.