Here are some measurements made with BabelColor CT&A:
The paper is Permajet Portrait White, printed with Perceptual. I had two profiles made with each program, measured 5 times each and then averaged:
Profilemaker 1:
C: 1,56
M: 1,59
Y: 1,62
K: 1,57
Profilemaker 2:
C: 1,56
M: 1,59
Y: 1,62
K: 1,57
i1Profiler 1:
C: 1,49
M: 1,48
Y: 1,46
K: 1,49
i1Profiler 2:
C: 1,48
M: 1,48
Y: 1,46
K: 1,49
From these data it appears that i1Profiler tries to make a neutral black, sacrificing dmax, while Profilemaker simply gives the darkest black possible.
Judging by my eye (which is all that matters to me) - The Profilemaker ones seems to be neutral, or too black to really know what tint it is. (or by stretch ever so slighly warm) The i1Profiler blacks seems dark grey with a blue/cool tint. Tints aside, the Profilemaker blacks definitely looks nicer.