The damage bonus from this guild is invaluable. But another huge perk is that you get Bash level 15. This appears to greatly increase success with spellcasting in combat, as you have to bash your enemy away before casting.
We break from Barbarian's Guild to share infobreak from antiquity:
Today is: 22nd February (GMT), in history on the 22nd of February, 1810 AD the following birth happened:
Holger Simon Paulli: Composer