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Herman:

While retired now, I was for many years employed as a designer/ draftsman involved mostly with oil refinery and chemical plant equipment arrangement and what was known as Piping Design, more accurately the physical arrangement of piping systems.

Respecting pipe fabrication, we had to provide the fabricator with detail drawings and dimensions to 1/16 th of an inch. No way one could do these sorts of calculations with a slide rule, we used Smoley's Parallel Tables of Logs and Squares, this being long before the advent of electronic calculators. I came to celestial navigation late in the game, and in any event, I'm not a boating type. 

In any event, Slide Rules while  no longer much used had one great virtue, that being as follows. For a quick solution of numerical calculations, if the answers obtained with a slide rule were far removed from answers obtained via other methods of calculation, the answers obtained via "other" methods would usuaIly wrong.  I still have a number of slide rules laying around,  both "stick"or conventional, as well as circular, that I now and then pull out of storage, and run some numbers with, . Strange to note, 2 x 2 invariably end up equaling 4, using pencil and paper, electronic calculators or a slide rule. Respecting the devices you mentioned, I'm unfamiliar with them, though no doubt, they served.