I tend to play Corruptors more than Defenders because they fit the concept better.
I think of Defenders as a bit like Captain America, noble and doing what needs to be done but within certain constraints. Corruptors I view as more Batman like in that they're happy to dish out an extra bit of violence to make the villains pay for their devilish deeds. Also I do like seeing Scourge popping up as the pain comes down.
In regards to the damage numbers being mentioned in this topic, they don't take into account the ability of each AT to deliver the damage. Being ranged ATs Corruptors and Defenders can deal damage over a much larger area than their melee counterparts, they can also do this immediately without having to chase mobs down.
I feel that the devs have done a great job in balancing the ATs, something for everyone.