The DPS stats I am placing beside the weapons is the combined damage of all the cannons in said bank.
Lancers:
Nolane Converter
Axial: 1 super heavy beam cannon 30 DPS
Fore: four heavy plasma cannons 65 DPS
Port/Starboard: Two light laser cannons 10 DPS
PsiTech Ranging: Increases range of all weapons (passively) by 10%/20%/30%.
Charged Cannons: Increases weapon damage by 35%/45%/55% and increase cooldown by 10% for 20 seconds. Costs 45/40/40 AM
Apocalypse Summoner: Activates axial cannon and deals 100/200/300 DPS for 4/5/6 seconds. Costs 120 AM
Astrom Lancer
Axial: 1 super heavy laser cannon 60 DPS
Fore: 4 heavy autocannons 60 DPS
Port/Starboard: two light autocannons 12 DPS
Maximum Firepower: Increases damage of all weapons by 100%/120%/140% for five seconds. Costs 60/65/50 AM
Focus Fire: increases damage done by nearby ships by 10%/20%/30% for 30 seconds. Costs 75/70/65 AM.
Railgun: Activates axial cannon and deals 350/900/1650 damage to the target. Costs 120 AM
Rashnak Obliterator
Axial: 1 super heavy pulse beam cannon 90 DPS
Fore: 4 heavy phase missile launch tubes 50 DPS
Port/Starboard: 2 light pulse beam cannons 14 DPS
Phase Cloaking: Phases self out, reducing incoming damage by 50%/60%/70% for 4/5/6 seconds. Costs 90/85/80 AM
Nanite Slugs: causes all weapons to yield a 2/3.5/6 DPS to the target for 10 seconds. (Passive)
Obliteration Cannon: Activates axial cannon and damages the target for 500/1200/2100. Costs 140/130/120 AM
Now just for the record, axial cannons will go down in the code as an actual weapon which is fired normally. Only when using the prime cannon abilities does it function as a true superweapon... Another thing to keep in mind is these ships have massive, long range forward guns, but can easily be outflanked. They are good for the first volley of damage in a fight and for focus firing. These ships also have an increased crystal cost (just as destroyers require more metal than normal).
As far as shape goes, they are long and cylindrical. Essentially, you took a cannon and put engines on it. Think of it that way... For this reason, they are slow at turning, but can accelerate linearly very well and have a very high top speed for a ship its size.
OH!!! and something that I forgot about... When charging/using the axial cannon, all weapons are disabled (as well as engines and the like)
So, now the general order goes as follows...
Cobalt<Kodiak<Gartel<Kol
LRM<Astrom
I suppose that is the best way to think of them. They are an LRM's big brother.
The most important thing to remember is not to get caught in this thing's sights. Once you enter the 20 degree forward firing arc (I want it small for the reason below), you are doomed. Between the Axial cannon's ability, its normal fire, or even the other four forward cannons, it can rip any ship to shreds. That said, If you are facing them, the best thing you can to is flank them. They have little defense on their sides and by flying circles around them, you can make your life much easier. Because of their added range though, they will hang back and snipe.
If your opponent has just one or two, send small groups of ships to harass them until they have to retreat or are destroyed. You can't win so long as your enemy has these things up and running... If your enemy has 4+, I would recommend an immediate tactical retreat... These things in large numbers would be by far the most devastating thing on the field. Now, of course they do require a command crew so you won't see too many of them, but all the same, don't underestimate them. They have the offensive power of seven HC's plus abilities so anything they aim at will die. Knocking these things out must be your first order of business (unless there is a level 6 Marza too at which point your first order of business should be running away) as they will singlehandedly destroy your fleet.