Pierciing Ice or Frost Channeling

[Shigeru]

I am currently a 30/21 Frost/Arc mage and i love my build to bits. I currently have 3/3 Frost channeling and i have roughly +212 spell damage. I am curious as to whether i should keep the frost channeling or change it for piercing ice and get an extra 6% damage.

Please give me your ideas on what would be better.

[kaiser]

well 6% damage vs 15% less mana is 6% better bolts vs 15% unless you are in a rush to do damage (pvp) the 15% less mana is better in my opinion.