The stock tires are Dunlop 218's - you can't even buy them. Personally I think they're garbage & I hate them.
I rode with Metzeler Sportec M-1's on my 750 last year, and I'm getting them again for my 600 this year. I saw a tire review which rated these 2nd best tires over a group of other very commonly used tires. The #1's were the Pirelli Diablos apparently - never ran those though so I don't know if they're really that good.
I bought my 600 for track use only. It came with the 218's. They are hands down the worst tire I've ever experienced. I wouldn't even dream of taking them on the track. They felt like an accident waiting to happen.
see, thats the problem. If the thread starter was a track star, he wouldnt even be asking this question.
Just going by this thread and so forth, i can tell the experience level isnt up there. which is fine. Hence why i said what i said.
Depending on the miles on those 218s, i would say run with them.