According to Ray, even with a SE input you are still getting a balanced out if you are using the balanced out. I will say that the soundstage does open significantly with balanced. As far as trying to decide what actual benefits you get from balaced in to balanced out I'm still working on.
My problem is I switched a lot of stuff very quickly so I'm trying to very careful about which piece of equipment I feel is responsible for what aspect. I went from SE Westone UM3x's and single ended 880's with a Little Dot MKIV to the Sr-71B, balanced 880's then balanced ES-5's and from there immediately jumped into balanced inputs, a new DAC and then the LCD's so I'm still trying to sort everything out.
As far as I'm really willing to go now is that with all three of the headphones I have plus a couple others I've tried it with, the SR-71B has only enhanced. Prior to this round I was doing single ended with Grado RS-1's and Senn HD650's with a tube amp (Raptor). So it's all been a three year blur. On top of that I got back into speakers too. So I am very careful about trying to steer peoiple in one direction or the other. However I feel the balanced route is definately superior