I have been using my little Chrony since about 1990 same one, 10's of thousands of rounds over it and it is still working very well, in fact was using it yesterday, like the bunny takes a licking and keeps on ticking
I always wonder how shooters with inexpensive chronographs know they're accurate.
For my job, they have to be, which is why I've owned an Oehler 35P for many years. All the other chronographs I use are tested directly against the Oehler. The three Shooting Chronys I've owned have not worked out in the long run--though in one instance the problem was a .41 Magnum bullet through the center of the display. But the other two eventually ended up being erratic.
