My main has always been a Shaman and for the majority of the last few expacs ele has been my spec. I don't remember having any huge issues leveling. I have one of each at 90 and I can say that it wasn't the easiest, it certainly wasn't the hardest.. Leveling my rogue was the worst.
Pet classes just zzzz it. Literally pull all the mobs you can see and smash em down. Quests done in 1 pull and all that extra exp.