6 figures in a unit at 2 attack each or 2 figures at 6 attack each? Is there a difference?

In terms of offensive power they'll both start out the same, but each has different advantages depending on the situation and how things develop. For the unit with only figures each unit will probably have significantly more HP than each individual figure in the six-figure unit, so the two figure unit can take more punishment in battle before their attack output starts to drop. On the other hand, things that can boost attack of units (such as increasing in level, magic/mithril/adamantine weapons, or various buffs) will boost the overall attack of the 6-figure unit much more than that of the 2-figure unit (as a +1 boost to attack will apply to each figure individually).

Due to this latter point, units with more figures tend to be more powerful towards the end of the game (as they increase in level, and you get access to more things to boost unit attack power), while units with fewer but stronger figures tend to be more useful towards the beginning of the game, when you don't have easy access to attack power boosts, and when you'll be getting into more close fights that will result in your units taking a fair amount of damage before the battle ends.

I always got the impression that lesser figures but more damage per figure was better though.

Ive tried using veteran draconian halbrediers with adamantinium weapons...on paper they should have 40+ attack with giant strength, a hit rate of 60% and a firebreath of something like 2 each.. I found that they had serious problems winning 1v1 fights against gargoyles, and those only have 10 defence each.

Take a look at this guide which while not perfect, gives a lot of information.
The section on how multi-figure units work is 4.5

As far as i can tell all 6 figures in a unit attack at once, but if the target consists of multiple figures, each new figure gets a new defence roll.

I dont really see how that penalizes attackers that are multi figure units though.

Gargoyles may not be the best unit to test against, as if memory serves they have a stoning attack which can quickly wipe out units that individually do not have high resistance.

All 6 figures roll at once, but they do not roll as one. A 6 figure 3 strength attacker generates 6 attacks at 3 strength each. Those will generate on average a single hit each (actually less than that), and will be very unlikely to damage a defender with lots of shields at all. A single figure unit with a high-ish attack strength of 12 will be much better at penetrating shields, even though it generates much less raw damage. I don't think gargoyles have a stoning attack - that's basilisks and cockatrices. Gargoyles do, however, have lots of shields, which are exactly the thing that multi-figure units are weak against.

They do not roll at once, there is a separate roll for each figure. Otherwise you are right.

If the figure has 6 figures, there are 6 rounds of:
1) attack roll => raw damage
2) defense roll => blocked damage
3) 1-2 = penetrated damage
4) each defending figure rolls its shields before taking any damage 2 units with 6 shields always deal a bit more damage, which is clear from the "damage matrxi" on the 437 page of Official standard guide to MoM.

but elite halfling anything lead by a demigod with leadership and an archangle, outfitted with magic weapons, are a good example of a crazy powerful stack to this rule. heck, even without an angle they still dominate. an bonus of 8*leadership on a 70%hit is nasty...

as the great parson taught us "its all about stacking bonus on bonus"
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