RCV: Standard convention is that a + sign is a bonus and a - sign is a
negative, even if the AC system seems to work backwards... :)
Just remember that the bonuses and penalties listed in the weapons vs
armor types are THAC0 mods, not AC mods; so that leather +2 vs piercing
means your opponent gets a +2 to hit you!
So +1 Studded is vastly superior to +2 Leather, except for the +1 to
saving throws over the studded that leather gives in this case.
The biggest thing, IMO is the piercing, ie arrow damage modifier.
Studded is better than leather at stopping arrows, ie it has +1 magic
bonus and a -1 to enemy THAC0, in effect a - 2 to hit vs AC 7 or an
effective AC of 5, while +2 Leather has a base of AC 8, made two steps
better by the +2 agical adjustment [AC 6] and then a +2 to opponents
THAC0, meaning it is worth AC 8 versus piercing weapons.
All in all, go for the +1 studded over the +2 Leather. Rich
AC modifiers! I got confused at times and need to exercise the very few
common sense I have :) Leather should be more vulnerable to piercing
weapons than studded leather, right?