Looks like the Ping i525 & i59 have MPF's published. The i525 #6 iron is a 327 MPF - Classic. The i59 #6 iron is a 103 MPF - Player Classic. I'm very surprised that Ping's older "i" series (i25...
FYI - The Taylormade Shaft Adjustment Sleeve Tuning Manual does say that the Lie Angle will be adjusted by 4 degrees from 60° in the Upright Position to 56° in the Standard Sleeve Position. Not 6 degrees....