I'm not sure I'd say the mini-torri is more prominent midrange. If anything it would be the base that is more prominent on the tori and the mids to highs on the Taboo, but the differences between the two really seem to be more matters of voicing than limitation. Both amps are quite capable through out the entire spectrum.
I was also going to add, before the Decware web site went down (that wasn't only me I hope) is that with the Taboo/CSP2+ you are getting not one but two headphone amps. One with cross-feed and one without. I'm not positive about it but I am pretty sure that your headphones would be happy with either. You might need to talk to Steve to be sure about that though.
Another thing I wanted to mention about Taboo/CSP2+ warmth. Like Rivierranch said, the CSP2+ with 6N1P-EV is quite warm, which is nice for many of the typical DACs that are available. In my case, though, my DAC is itself quite musical and warm so much so that I found the CSP2+ with stock tubes to be too much of a good thing. I ended up taking the CSP2+ out of the system for quite a while until I happened to talk to will about it and he suggested I try 6DJ8/7DJ8 tubes for a less colored, more transparent CSP2+ and he was right. I have put the CSP2+ back into the system, most of the time any way... Also, for what it's worth, I purchased a pair new Genelex ECC82 (12AU7) to try in the Mini-Torii and Taboo and it is quickly becoming my favorite input tube for both. It is very musical, yet detailed and clear, and packs a nice punch throughout the entire frequency range. I am quite taken with it. Now, the only input tubes I haven't tried that I really want to are NOS Mullards like RR mentioned, either 12AT7 or 12AU7s.
At any rate, good luck with your decision. It is not an easy one to make