I have a Tanglewood 12, and it came with an almost perfect setup. I was surprised, having previously bought a D28, and been disappointed that a guitar of this calibre needed setting up properly, after purchase.
I tune to concert, but I use light gauge strings, if you use heavier, then you would need to tune down to compensate. Tanglewoods are supplied with Elixir lights, and tuned to concert. So I would suggest that they are designed to be played that way.
I use an electronic tuner, but I find that the guitar isn't always in tune with itself when I use it, and it needs tweaking, by checking the fourths fifths and harmonics.