I was asked to write a review of my upgrade by a fellow member but I don't think I can at this time , I had only upgraded the trans in late March of this year. My kit was built back in 1999 , I had upgraded all the internal components thru the years , including copper foil caps , cerafine filament caps , AN-v cables , tantalum resisotrs , etc.... but the C-core trans was the only upgrade , IMHO , that had an immediate improvement sonically. I hope this was helpful , Jean-Claude .