After a turbulent yet successful first year of starting from Haren and Blanton I wanted to look at their stats vs. Hudson and Mulder's. I'll throw in Zito and Harden's numbers for fun. Here's the minor league totals according to thebaseballcube.com and the ages are their first season with 10+ starts.
Old Aces era h9 hr9 w9 k9 whip ip age
Hudson 3.55 7.17 0.43 4.32 9.00 1.28 271.0 24
Mulder 4.14 10.97 *** 2.30 5.72 1.47 137.0 22
Zito 3.18 7.20 0.37 4.24 9.95 1.27 170.0 22
New Aces era h9 hr9 w9 k9 whip ip age
Harden 2.99 6.46 0.40 4.06 10.89 1.17 337.1 21
Haren 3.15 8.49 0.89 1.63 8.76 1.12 474.2 22
Blanton 3.33 8.60 0.52 1.68 8.33 1.14 365.1 24
Here's their first seasons with 30+ starts.
Old Aces era ip h k bb
Hudson 4.14 202.1 169 169 82
Mulder 3.45 229.1 214 153 51
Zito 3.49 214.1 184 205 80
New Aces era ip h k bb
Harden 3.99 190.2 171 167 81
Haren 3.73 217.0 212 163 53
Blanton 3.53 209.1 178 116 67