I would go with...

Spyderco - Military, Para, or Chinook3
Benchmade - 710 or Rift
Kershaw - Blur or Junkyard Dog

But there's really a ton of factor's that can play into this.

Do you care about type of lock? handle material? what blade length laws are you bound to? what type of uniform work do you do? how much are you willing to spend? ect, ect, ect...