I use CODEs on one VHF, and it only has two equipped (Thor's Hammers). The other four slots are occupied by shieldbusters and missiles.
This is the only scenario (save certain Bomber setups) where I've found Codename guns to be useful. You can do respectable damage with just a pair of the hard-hitting types, 'course.. Those are so slow it really depends on your aim.
Other Codenames just waste energy. If you're looking for raw efficiency/power, go with the Nomad Energy Cannons (just make sure it makes sense for your character roleplaywise).