Thinking of selling my 5D MK II and moving to an X-E1. Want advice.

Definitely run both. I have an X100 and kept my DSLR's and boy I'm glad I did.  And the X100 has an OVF, though it's accuracy leaves a lot to be desired.  (Which I knew about, but in the long run having an accurate OVF in the DSLR's was a godsend I didn't fully appreciate.) But the bottom line is this: The desire for a smaller camera kinda comes and goes when you have both. You probably really want the option rather than a replacement.