Which one is the best GPU

A lot depends on what you are gonna be using it for, but out of those four I would recommend picking one of the 7870s, either the MSI or the ASUS as I have had favorable experiences with both.

Best not factoring in price? or are they all priced the same? Normally the GTX 660's are $20-$30 cheaper...

i will using for gaming... just tell which one...

Hmm

Really depends if you have plans about overclocking or not. I would say out of the box on the paper I would probably chosse the GTX660. But 7870 cards are known to be able to overclock quite a bit and a successful overclock of the 7870 will outperform the GTX660. If you are a overclocker and don't care about PhysX I would go with the 7870 from ASUS or MSI.

Actually I would by the 7870 and overclock it if I would find it necessary.

Go and buy PowerColor 7870 myst... this card is like gtx 660ti,this card have tahite le chip like card from 79xx series.. for gaming will be the best.. trust me