So, after reading the thoughts of other people (not through telepathy, but on this forum) I decided to replace the front tyre on my 600 with a Pilot Road 3.
What a difference!
I had a Continental Contimotion on there before, fitted by the previous owner, that had done about 1500 miles.
The front is now smoother, does not wobble at every ripple in the road and, more importantly, I have so much more confidence in the front end. Tip the bike in to the corner and it just grips and grips and grips! (Don't worry, Im old enough not to be over confident with it!)
Just need to save some pennies up to replace the square rear!