this info will help out a lot of new guys when they finally grasp that they can overequip their smgs and armor by getting buffed into them. the oe patch was a few months ago, so probably the newer folks aren't familiar with the exact formula behind it. it's listed in this article:
http://community.anarchy-online.com/...articles/2540L
the summary of the formula is as follows:
OE = 100 - (Your Buffed Skill or Ability / Requirement in Same Skill) x 100. If this formula yields 20 or higher, your weapon is over-equipped.... All armour more than 20% over-equipped, will be reduced in protective ability by 25%.... All weapons more than 20% over-equipped will have DamageBonus, DamageMin and DamageMax reduced with 25%.... All armour, weapons or pets will regain their formal status once the requirements are met again....
so, n00bs, get those wrangles and riot controls (and tip!) and oe those smgs. but be conscious of where the oe line is drawn so that you won't need a constant wrangle to keep your gun up. and don't count on the suppressor line from a fixer friend to help you out, as they are self only.
good luck!
important edit:
The 25% reduction in efficiency on weapons and armour will happen for each step of 20% that you over-equip.