The signature 2 one is the obvious choice, it has a better cooling system and higher overclock from factory, and it's actually cheaper(without the rebate).
You should also consider the 660 ti msi power edition, the ftw signature and that one are the best 660 ti.
 

coreempulse

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Jan 14, 2013
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I agree with djangoringo (above me) You should either go with the signature 2, or look at an msi power edition. Those cards (both) have great cooling, and are oc'd (room for more)