I've never tried the Sensation XE, but I did have the original Sensation for a while before I sold it. The sound was better then some other phones I've tried, but at the end I ended up going to the Galaxy S Vibrant instead.
As for the OP's question, voodoo control should give you more volume then you'll ever need.
I actually feel like the GalaxyS phones are really underrated as portable sources. I actually prefer the sound of my Q701s direct from my Vibrant over my budget DACs (musiland 02 and fiio e10).







