i bought a digital 600 last month,cost over 300 dollars,bought a magnetic used 600 ballast for 60 dollars,i see know differance,and the galaxy 600 digital does give off alot of heat,it is the last digital i dish out money for,i dont think they are worth the steep price.maybe they are cheap in the us but not here,alot of hydro stores dont sell them here they say they are a ripp off and have problems,just my 2 cents.