Zu beats Peregrine on install cost alone. Being more efficient on anything that isn't Strength 2, 5, or 8 is just another nail in the coffin. (They're even on Strength 0-1, 4, and 7, and Zu wins on Strength 3, 6, and 9. Notable 6 strength Code Gates are Archangel and DNA Tracker. Strength 3 Code Gates aren't really played. Magnet and Aiki are the closest to being played a lot. Against Zu, Enigma and Tollbooth are often played. Still, you have to run through an Enigma four times before you're even with Peregrine because of install cost.)
I do think it's interesting that the birds are (slightly) better than Aurora/Peacock, though.
Mostly what I was getting at is that Corroder vs Saker feels closer than Zu vs Peregrine. (Because Barriers are either trivial speedbumps to both (Wraparound/Resistor/Vanilla) or expensive enough that the Derez ability matters. (Hive, Curtain Wall)) So, if you're going to spend influence for a breaker and want the greatest impact, grabbing a Code Gate breaker is your best bet. Especially if you grab Yog and Datasuckers are your plan... (Just beware of Lotus Fields.)