When I managed the store (1977-1988), we were a Gibson, Martin, Guild, Ovation, Yamaha, and Takamine dealer. Fortunately, the owner had been a long-time fan of Guilds so we always kept a good stock of them. Gibsons however, were more of a problem. First, the company was (and seemingly still is) a terrible company with which to do business. They'd come in and tell us we needed to have an L5 and a Super 400 on the wall (when a Les Paul was going for $500, these were $2500 insturments- in a small college town...).
Anyway, one of my sales pitches was "I can make this Guild sound just like that Gibson." And I'd strum a chord on the Guild, then put the palm of my hand down on the lower bout of the guitar while the chord was ringing, killing all the top vibrations. And the Guild F-40 would sound like a Hummingbird...
The thing is, there's a lot of subjectvity in acoustic guitars. I've never played a Gibson acoustic that sounded right to me. But I've heard a few- I do like Pete Townsend's acoustic sound, and the Beatles' sounds- both of which are very much Gibsons. But my idea of a great acoustic sound is more from Stephen Stills and Neil Young- especially the studio recordings of "Helplessly Hoping", "Suite: Judy Blue Eyes", "Tell Me Why", "Old Man", and the live version of "The Needle And The Damage Done".
About ten years ago I was at a local store that had both Gibson and Guilds, and two guys worked there who also operated a good local recording studio. Tony in particular had great ears for sounds. I was playing a new Guild D-40 and when I started playing "You've Got To Hide Your Love Away", he remarked how much that guitar filled space like a Gibson J-60, only with more warmth.
John