bs, terribly thought out. kakashi wont know anything about kirin, first off he isnt that fast. and for him to be able to warp away kirin he must look at it for a while. kirin zaps down at the speed of light. boom goes kakashi.
It doesn't matter if Kakashi won't know anything about Kirin. Whenever a ninja faces another ninja, they frequently know nothing at all about their enemy's techniques. Kakashi knew nothing about Pain's abilities, but he found out that there was a 5 second recharge period between Pain's gravity blasts. Kakashi's analytical skills are very advanced, and the last time that Sasuke used Kirin, he explained all of its details to Itachi before it actually hit him.
Kakashi's cut lightning in half before with Raikiri (or so the story goes). Doing it again won't be much of a challenge. And with his sharingan, his reaction speed is much faster, so he'll totally be able to hit the lightning with Raikiri.
But it isn't about who would win, Kakashi vs. Sasuke. It's about Raikiri vs. Kirin.
Personally, I like Raikiri more, I think it's stronger. And it's certainly more versatile than Kirin.