As far as the Gibson dealer's story goes, I have a story of my own: I used to own 2 Gibson Les Paul Custom guitars, one made in 1968, one from 1971 or 72 - never quite got that one straight. I own a Gibson Les Paul Special and an Epiphone G400 Custom/Les Paul SG today.
The quality of the hardware, construction and materials on my Chinese Epiphone is as good as the '68 - except for teh cheap looking plastic inlays on the fingerboard of the Epi. The Gibsons were real MOP. The actual construction and design of the '71 Custom was not as good as my 2007 Epiphone and not as good as my '02 Special, either.
So far as I can tell,the actual wood - mahogany - used in my SG-style Epiphone is first rate .It sings and rings, and I can hear my wife finger-picking it unplugged from across our living room, and I love to feel the vibrations through the entire instrument whenever I play it. It is one of my favorite guitars of my 50 some years of playing.
The gold plated hardware, Grover tuners and pickups are as good as the Gibson versions I remember from years ago-I think the pup's tone may be slightly different, but Epiphones have always sounded different from Gibsons, even models from back in the old days. There is almost no difference in quality that I can tell at all.
Plywood tops: The old Gibson jazz hollow body guitars were first made using a carved solid spruce top, later - in the '60's, IIRC, some -such as the Barney Kessel Model-were made with the laminate top. They were several hundred dollars less, and supposedly "inferior" because they did not change tone or "mellow" over time. Turns out they do anyway, more slowly, and they don't split or crack.
I used to work in a guitar shop, and have played maybe 40 differeng electric guitars, and I don't believe the story about the "cost of the wood" - the difference per guitar would be about $75, maybe.
Play a few Epiphones and I have little doubt you will be very happy with them
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