Dan,
   My 2 cents worth is to takeoff if need be from where you are and after
orbiting long enough to make sure everything's "in the green", move to a
field with a bigger runway until you've got at least ten hours on the plane
and several landings under your belt.  I'd also be reluctant to land on a
short runway until your brakes have been fully broken in and you're
comfortable with them.
   Most of us who have flown these things will attest that landing rollouts
take some getting used to because the brakes aren't the most effective I've
ever had.  You also need to fly a bit and make sure there aren't any bubbles
in your brake lines, which often show up after they expand as you climb.
I'm speaking from personal experience here.  The first time it happened, my
left brake just mushed to the stop and I had to go around while I pumped it
up.
   When I got my airworthiness certificate, I wasn't allowed to do test
flights from the field where I built my ES due to the population in the
surrounding area.  I was given a one time ferry permit to take off and fly
to another field which was located within my approved test area.  If Potomac
is in a densly populated area, this is likely what you'll have to do as
well.
   Best to play it safe until your plane is tested.  Once it is, 2600' is
plenty for an ES.
   Good luck,
   Skip Slater
   N540ES