I assume you aren’t talking about the stats, cause that’s easy.
- Spellpower +40 to all spell damage schools
- Sunfire +50 to fire only spells.
So you miss out on 10 damage for fire spells, but pick up 40 damage on the other schools (assuming you are a Mage, Arcane and Frost).
Cost wise (and expansion wise) spellpower is the better enchant. (more…)