Does it give wrong values? Lose zero? Why don't you trust it?
My Harbor Freight 6" digital calipers have been relatively good, I used to buy them for $9.99 when they were on sale. Of course, they aren't $9.99 anymore, but they are ok for shop use. For real measurements, I use a micrometer. So anyways, thought I would take a chance on them, better than reading 1/8" marks off the tailstock.
Edit: Just measured a piece of keystock with my Starrett dial caliper, I got 0.374". With the $12.99 caliper I got 0.374". Hardly definitive, but not so bad. Measured the thickness of my No. 305R Starrett scale at 0.0165" on both. I'd expect that both calipers need to have their zeros checked, but so far it is ok.