Help buying laptop for $600

Hi,

Am planning to buy a laptop in US for a budget of $600 or less. I am not into gaming stuffs.

I'm confused among these. If you could give you comments on these it would be very much helpful.

1) Lenovo Think pad $532
2) Lenovo Ideapad $549
3) Inspiron 14R $549
4) Lenovo G470 $549
5) Inspiron 14R $599

There is not strict requirement that I would require a i5 proc. Open to you suggestions.

Thanks.