I always went primarily with the armour class for armour, then looked at other bonuses. However, you do not get hit in the head much (a helmet's chance of blocking is something like 10% IIRC), so the armour class isn't a big deal. The higher AC helmet will absorb more damage if you get hit in the head, while the other will give a bonus all the time. I'd go for the 70 AC, but if you are early enough in the game that 10 HP is a nice bonus, then that wouldn't be a bad choice.
I don't know the formulas used to calculate damage, but your offense and defense are calculated from your agility, and depend on character class. Your chance to hit / be hit are based on agility and character level (I didn't try figuring out the formula used, but there is an example in the topic below). I assume both your character and your opponent's hit percentages and are used during the combat calculations.
differences between classes (minor spoilers)
Thanks Raze. I am trying to figure out what would be a good agility to have at lets say level 3.
At level 50, it says that an agility of 150 is needed for 94% hit rate.
Now does this mean I will hit the enemy 94% of the time, regardless of who the enemy is?
I see that the agility is nearly 3x the level, though I doubt having an agility of 9 at level 3, would ensure that I hit 94% of the time.
I am sure there is a more of curving exponential factor or something of that sort.
If you do happen to find out the exact formula or know what I agility I need at lower levels to max hit, let me know.
(I love numbers. <img src="/ubbthreads/images/graemlins/biggrin.gif" alt="" />
Trying to make a mean Poison Warrior.