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The place where digital calipers really win is in measuring the center-to-center distance of two holes of the same diameter. Measure the ID of one hole with the horns, zero it in that position, and then shift to one horn in each of the two holes, pressing against the opposite sides. Now you have a direct reading of the center distance between the two holes. It even automatically compensates for the chord error from the fact that the horns don't have fully sharp edges.
Another benefit, at least compared to most dial calipers, is the ability to measure in either inch or metric units at will, and to convert back and forth between them. Yes, there are dial calipers with two hands and concentric scales which read in both systems, but getting both to zero at precisely the same point is tricky. (Maybe someone makes really good ones which have no problems there, but the ones which I have seen leave something to be desired there.
FWIW -- what I have:
1 4" dial caliper -- Helios (new -- decades ago) 1 6" dial caliper -- Phase II (new) 1 150mm dial caliper -- Starrett (new) 1 6"/150mm vernier caliper -- I forget the brand. (new) 1 24"/600mm vernier caliper -- Scherr-Tumico (used, hamfest) 1 12"/300mm digital caliper -- Mitutoyo. (new, hamfest) 3 6"/150mm digital calipers -- Mitutoyo, Starrett and nameless import all bought used except for the nameless import -- all working using induction/capacitive scales. 2 Browne & Sharpe (likely really Tessa) 6"/150mm digital calipers with glass scales. Both are semi-retired for the moment -- until I make new battery compartments for them to run from a pair of CR2032 3V cells instead of four PX-13 mercury cells -- now made of unobtanium. I've verified that they work fine at the higher voltage, so it is just a matter of making the replacement battery compartment. One of these was from a hamfest back when the batteries were still available, and the other from a tool flea market much later.With a resolution of 0.0005", the digital calipers are close enough once you develop the proper feel to avoid cocking the moving jaw. And "feel" is a matter of importance in micrometers, too -- especially those from before the friction thimbles or the ratchet spinner. Too many micrometers to list, but they go up to 12" at the top end. And one 25mm one from Russia, which is about 50% more massive than any US made 0-1" micrometers. :-)
Yes -- I use the micrometers when precision is really important, but for many things the digital calipers are quite all that I need.
Enjoy, DoN.