I have revceived the acoustic version now and am able to compare both the Kingpin and the acoustic one. So here are some more comments on the tone of the 5th Avenue.
First I must say that I was never really pleased with the sound of other steelstring acoustics that I played. My background is that of classical guitar training when I was a student and of playing the electric guitar most of the time nowadays. I always wanted a steel string guitar that was closer to the playability and sound of an electric guitar than my Yamaha APX-4A flattop was. I had only once played an acoustic archtop before. This sounded interesting but was not a quality instrument.
Now the difference between the acoustic 5th Avenue and a common flattop guitar is that the 5th Avenue is not as loud - yet loud enough to accompany one´s singing. There is less bass and treble and more mids, so the sound is a little warmer and indeed closer to an electric guitar´s sound than that of a flattop acoustic. Of all steelstring acoustics I have heard, this is the one I like most so far, although I will not turn into a folk picker now

...
The major strength of the 5th Avenue is its incredible playability. The neck feels wonderful and is very fast. What I do not like about it is the electric sound of the Kingpin´s P90 pickup. I had prefered a warmer, jazzier tone, instead it has a thin, dull bluessound, that some people might like. I do not like it. I think you would be far better of with the acoustic version and a floating jazz humbucker mounted to the pickguard or neck. This is why I ordered the acoustic version as well - also hoping that the acoustic sound of it might be even better than that of the Kingpin. The use as an acoustic guitar to accompany my singing is the main purpose why I bought this guitar - I simply was not happy with my old Yamaha APX-4A and wanted something else.
So now I have got two 5th Avenues: one Kingpin, one acoustic. I have to decide which one of the two I will keep and which one I will return. There is not a big difference in the construction of the two guitars as I had falsely suspected before. What I had mistaken for a solid piece of wood underneath the pickup of the Kingpin simply seems to be the inner bracing of the guitar. It is there on both versions.
The differences between the two guitars are:
- For some reasons they have used thinner fretwire for the Kingpin, which I like.
- The acoustic version has a rosewood bridge while that of the Kingpin is plastic. The rosewood might sound better, the plastic one feels better if you rest your hand on it.
- The neck wood looks better on the Kingpin.
- The acoustic sound of the acoustic version is more balanced and a little louder, but this might be because of the phosphor bronze acoustic guitar strings that are on it as opposed to the roundwound nickel electric guitar strings on the Kingpin.
Which one should I keep - I really don´t know yet.