skysailor: I have an '11 F650GS (13K miles) and an '09 R1200GS (35K miles). I am 5'8", 170 pounds with a 29" inseam.
The F650GS has been modified with Ricor valves in the forks and an aftermarket shock in the rear and this improved the the bike a lot. I also raised the forks a tad (4mm) to shift a little more weight up front. I can flat foot the bike and it is a really nice ride with what I think is a great motor. When on dirt roads I think that first gear is a little too high and have to use the clutch a fair amount. Very easy and satisfiying bike to ride though.
The R1200GS has a Sargent Low seat that is a great improvement for me. I can't flat foot but I don't exactly tippy toe either. The R1200 is probably about 60 pounds heavier than the F650GS but it carries the weight low and is really easy to ride including on dirt roads.
Of the two bikes I honestly prefer the R1200. Try both the F700GS and the R1200 and keep an open mind.
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