It can, for example, tell you how much spell power an item with 36 int would actually give you and if that item would make you gain or lose that specific stat when equipped. Rating Buster : Rating Buster converts stats into ratings and allows you to quickly compare two items to see which one is the best for you. Addons I recommend these following addons while leveling (playing) your Priest:
Glyph of Shadow (level 20) - While in Shadowform, your non-periodic spell critical strikes increase your spell power by 30% of your Spirit for 10 sec. Glyph of Shadow Word: Pain (level 15) - The periodic damage ticks of your Shadow Word: Pain spell restore 1% of your base mana.
Glyph of Mind Flay (level 20) - Increases the damage done by your Mind Flay spell by 10% when your target is afflicted with Shadow Word: Pain.
