Hi mazian! I have two sterio pair of the PuriFi amp and six Starke AD4-320s.
The Starkes are just a bit smoother on the top end. The are designed for smoothness. Transparency, etc will depend more on your preamp, cables etc. The amps that have the "guts" in a tube bottle are also extremely clear and impressive. I don't own any of those but have contacts with them and Ocean Audio and have heard them under very good conditions. But they are pricy and the newest version of Starke's amp is going for $1500 and is the bargain of the age. I use 4 way electronic crossovers (miniDSP) feeding the four way Linkwitz LX 521 speakers on the main system. That takes care of 8 channels and two amps. Another Starke powers the rear speakers and center channel. Geninely awesome. I also use one of the Starkes (bridged stereo mode, 320 wpc) to power Magnepan LRS speakers. Another Starke powers a 5+1 surround sound system (with the help of two extra amp channels, LM3886 based - I have many of those). The Purfi amps feed a very good bedroom stereo system. One is now a spare and traveling demo unit. I won't disconnect the Starkes; they are too good to disturb. Cables matter; you will hear differences in cables if your front end is good enough. Feel free to contact me if I can be of service. Happy Listening!