I have had this little beauty (MC225) for over 20 years now. Its been a great addition and a stellar performer for my home studio. The MC-225 is a great amp for your collection or for daily listening. If you know and appreciate the craftsmanship that went into the design and building of these then you know McIntosh and will appreciate this great amp. I have the original owners manual, schematics, and even the original Service cards/business reply cards that McIntosh used to provide to the original owner. Arguably it is not in perfect condition and I've toyed with the idea of replacing the top plate with one of the shiny new chrome ones I see for sale on-line but for me, having a "original" feels better. That being said, I sadly cannot speak to the vintage of the tubes. I can only guess that some are original and some may have been replaced over the years - I honestly do not know. I have not needed to replace them and I can say that when the unit is powered down it does NOT have the white-noise fade, so common of a tube going bad. I hope you can appreciate and care for this unit the way have - I'm confident it will provide years of enjoyment.