just test-rode a FZS 1000 - lovely, but..

[fazersharp]

I say go for the 600. I'm thinking that perhaps, could it be the reason you think you need a 1000 is because of your experience on that old xj 600, the fazer 600 is a very different bike, and it will have plenty for you to "grow" in to. I've had mine for 12 years. I - like you am 5,8" and 91/2 -10 stone and its like the bike was made to measure and built for me. As for steering - remember that you don't just steer with your handlebars as you also steer with your body weight and that's where the (I think ) problem lies with the thou, its just too heavy in the corners unless you are a 15-18  stone lump. People moan about the 600s soft suspension --- but that too is perfect for my weight.
I wonder what the power to weight ratio is with me 9,1/2 stone on the fz 600 against an 18 stone chappy on the thou