That looks very nice :) I love the stuff. I think it is polymer based and really does build up quickly to a nice sheen. a light rub over inbetween coats is all you need to do. Anyone can get a good finish with this stuff its that good ;)
Always been tempted to build a guitar myself. I think the section of wood for sound board is something to do with how good a guitar is. This is a skill of the luthier that probably takes year to acquire..... so you get what you pay for and some of that is how experience and expertise!