All my chars were leveled via questing. Ive helped myself with a few quests(such as the one that gives you the crit trinket in hellfire and the mastery quests in nagrand) and instances but nothing too extreme.

I believe that questing is the best way to experience a new class, but ive got to the point that ive wasted enough time playing my 70s when i could be leveling my priest.

Im guessing that theres on other mega easy grinds such as the zolo grind anymore?

With regards to the RAF suggestion from my priest account: i was informed by a friend that you can no longer grant a retail account levels from a trial account anymore. Only once it is converted to a retail account can it be used to grant levels. Is this correct?