Since you don't have a direct reply. I can only say that I can't testify about the shaft. But I owned quite some Predator cues through the years.
What I can tell you, is that, most Predator cues within a certain serie, play more or less the same with the exception of little weight variances (assuming we're comparing the same weight class of cue each time) and therefore slight variances in cue balance.
There are some exceptions as for example the Ikon serie used different woods, so there was a bit more of a difference in hit. But Blak series are usually more or less all ebony and hit closely the same.
The difference in the bucks is there... and well, you end up paying for a bit more inlay here and there too I suppose.