Both ampilfiers sound simialar. The zeus has More power. I talked the Mark Obrian About mine he said its much more then 225 a side.Keep in mind this thing ships at 225 on a pallett/box, as the 150's are much easier.The power supplys are very overbuilt as well as the output xformers. Triode switch is right there to switch and sit, standby is nice, has dual low speed fans to keep circutry cool, Balanced input, and will dominate the room its in looks cool with the tube cage on also.I love mine. Blows the Hurricanes away as far as power, Cleaner then the vtl300's more refined then the rogue120's,smoother then AR Classic 60's,better match to the von schweikerts then the cary v12,ect.
The strong point is the midrange, lows then the highs.
The 150's and Zeus sound completly diffrent then the 120's not as solid state. Zeus has midrange to die for while speedy highs and taught lows. First tube amp i havent clipped yet... Illenema1@wmconnect.com