[GunMetal Black]

I don't know the difference between the EX and ZX models on the Ninja 650, and 600 models respectively. I want to know because I am looking to buy my first bike and the ZX costs 9580 New I think, and the EX costs $5480, also new, but they are 2007 models.
2007 Kawasaki Ninja ZX 600 - $9580

2007 Kawasaki Ninja EX 650 - $5480

These are the links (duh ) and I like the looks of both bikes.
What one would be good for a beginner rider, if either, and what one is a better deal?

I'm also considering some other makes of bikes, like the Suzuki SV650 naked.

Feedback would be appreciated!!!