xFIP Ages 23, 24, 25:
Porcello: 3.89, 3.19, 3.68 -- wtd average: 3.55
Zimmermann: 3.92 (31 IP), 3.78, 3.78 -- wtd average: 3.80
Ages 26:
Porcello: 3.72
Zimmermann: 3.48
My money is still on Porcello having the better (measured by xFIP or fWAR) next five years.