I heard the Sphinx in an audio shop here in Chicago. And it sounded great. A very impressive unit for the price.
Though, that said, I loved the sound of the Acoustic Zens I heard at Axpona with the tube amps they were paired with. I personally would go with a tubed integrated with the Acoustic Zens. The Rogue tube integrateds aren't too much more than the Sphinx. I would personally use the Sphinx much like I used my Butler 2250: for speakers that are less efficient and thus might make appropriate all-tibe gear cost prohibitive. But for a speaker at 90dB and up I would go all tube instead of hybrid if you are looking for some tube sound.
Though, that said, I loved the sound of the Acoustic Zens I heard at Axpona with the tube amps they were paired with. I personally would go with a tubed integrated with the Acoustic Zens. The Rogue tube integrateds aren't too much more than the Sphinx. I would personally use the Sphinx much like I used my Butler 2250: for speakers that are less efficient and thus might make appropriate all-tibe gear cost prohibitive. But for a speaker at 90dB and up I would go all tube instead of hybrid if you are looking for some tube sound.