MA or DM for all round pve
i have a lvl 50 MA/SR (softcapped at 3 positions) and a lvl 50 DM/Regen (a lot for recharge for the healings).... although ι consider my DM more powerfull, i have more fun playing with my MA
defiant only
@amartia
my public list : http://cit.cohtitan.com/profile/9355
Go DM/SD. At level 50, io'd out, you'll do more damage than MA all around because of soul drain and the fact you can tap into fire or mu for epics and fill in your aoe hole (although niether set has very good aoe anyway), along with some shield charge action. Then on top of that, you're survivability will be better thanks to siphon life.