Back when I was match director, the IL DNR bought us 6 of the Competitiom Electronics Pro timers I linked to above. One for each stage we would put on.
I never got any complaints from the shooters at my matches.
This is the Pact timer I have now:

When I hit the review button, it gives me some 1,746 second long split time. I had done a search on the BE forums about a year ago. Seems to be a common and well known problem.
IIRC, the fix was to take the battery out and put something metal across the connectors inside the timer.
That is supposed to clear out the memory or something???
I just never got around to it yet.