How to level different priests (long story) in various builds

Preface: I have leveled two priests (long story) in various builds. I'm not perfect, whatever the hell it'scalled nowdays patron saint of my realm; but I do have extensive experience.
   • Priest builds fall into two categories, generally: Pre-70 and Post-70.
Pre-70, you can pretty much heal effectively no matter what. Gear matters more than build. When you step in the doors of Karazhan, that changes (hence Post-70). This leads to the first general rule of priesting:
Level in Shadow (unless you have a GOOD reason not to).    • It's just more effective for soloing (if you have to or want to) / grinding / questing. And you can still heal without issue. I often showed up for a healing run in my healing gear and not in shadowform. After the cries of "wewt leet healz" after the end boss was downed, I loved to meld into shadowform and hearth after a hearty "thanks!"
   • You may notice, if you click my build icon in my portrait header, that I'm currently Disc/Holy. Yes, I had a good reason to respec. I'm mostly running instances or grinding out quests in a guild group for the rest of the climb to 70. I can benefit the party more now by buffs and healing. (And it's hard to make an effective dent in a 70's health bar heehee.) So mostly selfish reasons, I wanted a few more HPS in the instances.
   • Now, the meat of your question. Is Spirit of Redemption worthwhile. Yes. It's seconds of free healing. The drawback is that you have to die to get it...never leave home without a 'lock in your pocket. It is based on playstyle though. My build does not, and will not include SoR. I'm heavy into Disc for many reasons, because I like the playstyle I get. I also have holy talents that I like better than SoR. In my opinion the single greatest healing buff we have is the clearcasting state.
   • This leads into the second part of your question. Should you be Holy or Shadow? That's your call. Pick what you like and find an effective place. A shadowpriest with proper gear can be one of the best single-target DPS classes in the game. You can also highly buff Warlock shadow damage and the entire party with stabilizing mana and health regeneration.
   • On the other hand if you like to see Scrolling Combat Text racking up the green plusses over people's heads, try Holy or Disc/Holy. It's fun to watch a health bar snap from low to high with a well-timed crit heal...
   • I personally think that guilds that are not open to a two-priest Holy / Shadow combination are missing out... :: shrug ::