I've had many big singles but this is my first XF650. It's physically very big, which I consider a good thing, but crucially it's also very light too - there's a lot air under that fairing.
In comparison my FX650 (Vigor) feels small and dense compared to the Freewind large and leggy.
The engine is a slugger, not as happy at low revs as the Vigor but just as much mid range punch. I've no idea what the top end is like as I'll never rev it up there to find out.
The handling is good as described, I don't find the suspension soggy at all, but I have wound the rear preload up and changed the fork oil to 15W semi-synth.
The digital dash is nice, fuel gauge, revs and trip meter but as someone else mentioned a clock would have been nice.
Fuel economy is good, 60MPG and more is possible if just lolloping around.
The off road performance is great, that long suspension and loads of ground clearance really helps. The tank is scolloped so that you can stand straight legged and the high handlebars make sense when you're standing up, enabling you to ride with your back straight.
The bike is described as European and it definately feels like it was designed with large Germans in mind - the comfort level is superb, I'm 6'2" and I could ride this all day in comfort.
I like that it's a wet sump engine, which makes oil changes a lot easier and the screw and locknut tappets are child's play to adjust. Access is good once the tank is off.
Overall it's very good, compared to the BMW F650 which it competes against (and looks virtually identical to) it's lighter, just as fast, handles better and is mechanically less complex.