Bob Bobbleton on here had an '07 R1 from new, a number of issues with it, play in the swingarm bearing, buckled wheels etc. He chopped it in for a brand new Blade due to all the issues he had with it, so I'd avoid the 07/08 model of the R1.
As for the 750, they're nice
My 750 used less fuel than the 600 on this tour.
It'll also go round a track too:
Only difference is the position of the pegs and tyres fitted. An awesome do it all bike, but get what you want....