I much prefer mechanical ones to digital ones. for a mechanical one to fail on you there has to be something INCREADIBLY wrong to stop it from working where as a digital on can stop for any number of reasons. electrical short, bad programing, screen malfunction, sensor malfunction, etc.
now if a digital one were to come out that has less potential failure points than current mechanical dash boards then I would be all over that. or if the cost of trouble shooting and replacing faulty digital dashboards were significantly less then maybe. as it goes now if there is any sort of electrical failure in a car the whole system gets replaced not just the component that went bad (unless you do it yourself). so any electrical issues you are dealing with can easily cost thousands of dollars to fix even if it is just a bad $20 sensor.
although not electrical related a good chunk of my job as a hydraulics engineer is to reduce the total possible locations of hydraulic leaks and hydraulic failures thus making a better machine with less warranty issues and easier and cheaper fixes if there is any issues.
EDIT: I just remembered this but back in high school when my class first got our licenses one of my friends got a vehicle with a digital dashboard and we found out that it can be fooled into displaying a different speed by swapping from drive into neutral and back to drive while moving. it would display the return to drive as 0 mph and any speed up would increase the mph by the increased speed (resetting at 30 and speeding up to 45 would display 15 mph) but slowing down would keep the speed at 0 but if you went over a few minutes of going under your reset speed the dash would blank out. no speedometer, no engine rev, no temp, no mileage counter.