NO...They don't have to be exactly the same on a radiator, just get them close if you can.
Fans work like pumps, they are spinning their wheels so to speak against the air so a little mismatch is not going to hurt anything. The fan is capable of 70CFM in open air, yet under restriction it's only pushing 30CFM, If you add another fan in sereies capable of 60CFM and the combined output is still only 40CFM. Each fan could care less if they are matched or not as they are both operating well within their limits. You probably just want to avoid a huge mismatch (150CFM Delta and a 30CFM on very low restriction, etc.)
I've heard some people say otherwise, but I have yet to see any scientific test. Another one of many forum created myths...
From what I understand about pumps and fans, this is false.
I have seen several examples of operating similar but different pumps like a D5 + DDC, etc without any problems.
Air is very flexible and compressible...should be no problem mixing fans if they are roughly similar when operating against restriction like a radiator.
+1 on the P12s, they will be a step back in performance on the radiator vs the corsair.
Zalman F3 plus High Speed yates would be close enough I think.