Choice of 3 different Sony 13"?

Frys has a few of these Sonys with "Z" in the name.. Are all of these those fancy "Z" series everyone talks about? I have been having a really hard time choosing a new laptop, and i been thru a Samsung 15", Toshiba netbook, and Asus G73 so far.. I was stuck on the fact that i had to have a killer gaming machine, but im starting to release that hold. I have a good PC for that. I like the speed of the Sonys, the screens, and the SSD drives. Any tips on the 2 below if you had to choose one? (I removed one which is no longer available locally)



Sony Z13JGX/B 13.1" 1600 x 900

i5-460M 2.5-2.8ghz

4GB ram

GeForce GT 330M

64GB + 64GB SSD drives for 128GB total

$1899 (found for $1550 shipped new on ebay)



UPDATE: BOUGHT THIS ONE FOR $1949

Sony Signature Series Z13SGX/BJ 13.3" 1600 x 900

i7–640M 2.8-3.47GHz

4GB ram

GeForce GT 330M

64GB + 64GB SSD drives for 128GB total

$2099



So, is going from a i5-460M 2.5-2.8ghz to a i7–640M 2.8-3.47GHz worth the $200 more? From 2.8 peaks to 3.5 peaks seems like a pretty decent jump to me..