Hi,
I haven't personally, but there are quite a few models flying that are right at 700 in.2

I can't offer any real world examples yet but I'm currently building a Coasby Taurus. I think it's around 67" span. Not sure of the wing area but it must be "Up there". Flight report hopefully early 2013. Any thoughts on what to power this beast with gratefully received.

TTFN
John.

I recall someone built a 1/3 scale SIG C/L Spacewalker electric powered model. I don't recall who it was for certain but it might have been Mike Gretz? I do have the kit and I'm thinking ..................

As part of my RSM electric power system testing I took the LA .65 off my Top Flite Score and replaced it with an electric motor.  This plane weighed just over five pounds on gas and about the same on electric.  The electric motor weighed a lot less than the gas engine and muffler, but the battery was heavier than the full 12 ounce fuel tank but it was about a wash in the end. 

The plane flew great, I even used the same gas prop from the .65 and except for the sound the performance was as good or better.  I know in the R/C world they are using electric in 1/3 scale planes with great success.
Andy

Here are some info and images of the plane I am currently flying.

Tweener Design by Jose Modesto
WS: 64.5  equal panels
WA: 745
Weight: 64 oz
Stab & Elev. Impact, area: 164
Nose @ 11'', Tail @ 19"

Power Package
eFlite Power 32
Phoenix 60
FM9 Hubin Timer
Sky Lipo 3000 5c
13x5.5 apc e.pusher

Construction
Complete composite technology Wing, fuse and stab.
Wing has foam insert. no ribs, One hollow tube. There is only two half ribs for LG
Carbon fiber re-enforcement for wing tips and nose area (nose from inside)

Others
Lines 65 eye to eye
Kaz Handle 8.5 cm
Lap time 5.3

This is a Big Jim Tweener air foil (High aspect), Impact fuse, stab and Elev.
Very nice stunter, responsive, tight corners, nice line tension every where, blast to fly.

Special Thanks to:
Jose Modesto, for his teaching, his support, his knowledge and sharing, his coaching, his innovative approach to building.
William DeMauro, for sharing his expertise in electrical power system.

Juan Carlos
I wish I could provide a picture but I didn't take any.  It was just a short term project to test the motor for Eric Rule at RSM.  But what I did was very simple.  If you are familiar with the Score, here is what I did.  I removed the gas engine and the bolt on motor mounts.  I use the rear mounting cross on the electric motor and just bolted it to the firewall, very simple.  I don't think I would recommend this unless you reinforce the firewall with some fiberglass or carbon fiber.  Since it was a test setup I put the electronics where the fuel tank went and mounted the battery under the fuel tank compartment.  To my supprise the CG came out very close to where it was with the gas engine.  I had a very heavy LA .65 prior to the electric setup and the electric motor plus electronics and battery were about equal.

Any questions you can email me. 
Andy