Andy, I have finished about 25 guitars with Cardinal lacquer. Compared to the well-known brands such as Mohawk, Behlen, Seagrave/McFadden, the Cardinal seems to have a significantly higher solids content and hardens much faster. There is also less shrinkage & pore settling. I reduce about 5-10% and the finish builds quickly. As previously mentioned, solvent pop can be an issue if you get too heavy-handed with your applications.
I probably sand back more than necessary between applications but I don't think that a quart would be quite enough for your Bandura. I get about 3 guitars out of a gallon using very low pressure with Iwata guns.
Shelf life for nitro is typically years if you keep it cool, sealed and away from U.V.
Without sounding like I have a stake in Cardinal (I don't) the product is in a class of it's own. I get finishes that are near-perfect with significantly less labor and time than I was used to with other brands. I hope that Cardinal keeps making the stuff.
Mike Franks
www.mjfranksguitars.comwww.facebook.com/mjfranksguitars