except you get an 11% bonus to willpower when buffed and spec'd right, not to mention the over 1% crit you gain from augmenting wp
252*111% = rougly 280 (279,8)
Soool 1 bonus damage or 1% crit?
Even for class without that mainstat bonus, that extra crit is interesting since its on a different DR than your crit rating. The power sacrifice is just a no-brainer when its not even 1-2 damage per hit.