I would group in other MMOs to grind out XP. This game isn't geared towards an XP grind. The storyline missions give you enough XP to level. The game also gives us a companion to help (for what they are worth in some cases) with leveling. Other than the social aspect of grouping, which honestly isn't overly necessary, there's little to be gained. Now, if you're trying to learn a role in a less demanding setting such as tank or healer, maybe 2 person heroics or basic storyline questing is a good idea but for so many reasons already me tioned, I pass on "buddying up" for the basics.