Also considering trading in my DR650 for an F700GS and waiting for them to arrive at my local dealer. I have been for a spin on a F650GS which is same dimensions etc and was impressed how the bike handles and it felt like a bike I had ridden for years in the first couple of km's.
Also going to have a test ride on the F800 but after sitting on one today they do feel like a much bigger bike than the F650. From all what I have read on here and other forums it seems the F650/F700 is the pick for mostly road use. Also a $3000 difference in price here in Oz