Good luck with the 6k miles. I had my first rear get about 4,000 miles and then I replaced it before a 1800 mile trip because it was about 1mm to the wear bar. The front I'm sitting down at the wear bar at 8,000 miles, started to scallop bad around 4,000 miles, flattened out a little, the traction is ok, a little sketchy sometimes though for the last 4,000 miles. The second rear has 4,000 miles and looks like it's about to get down to the wear bar again. I've been a lot easier on it than the first but I'm guessing for 5,000 miles.
I had a set of PR2's and they were at 8,000 miles before I got a nail in teh rear. I could not stand them for sport riding, but they are solid for street riding, commuting. I'm gonna go for some PR3's next because I heard they have better stick than the 2's and am waiting for the T30's to be released in the US. There are some members on the Fz1 forum getting 18,000 miles out of a set of PR3's, average seems to be about 12,000 miles.