They're in line because Tyll is the one who does the measurements. The differences are that on innerfidelity.com, they are an average of 5 different locations on the dummy's head (so more accurate there). The 300Hz square wave plots on the K812s doesn't bode well.
The MAD Ear+HD is one amazing amp with the RS1i...I'll have to slum it with my GS-X Mk2. Actually a hell of a combo...I have yet to find a pair of headphones that don't sound spectacularly through this amp.