There are several other choices that aren't decades old designs, from what I understand, these are considered 4.5 gen fighters. 
 
F/A-18E/F Super Hornet 
F-15K Eagle 
F-15SG Eagle 
Su35 
Rafale 
Typhoon 
 
I don't think we need to be on the bleeding edge to have an effective air force.  Plus these are proven designs that would could buy now, instead of stretching our CF18's for another decade.
		 
		
		
		
		
		
		
		
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