My dad bought me a battery operated electric Peugeot pepper mill a while ago. It was utterly worthless and the motor died after a few months of light use. Reading reviews on Amazon made me realize this was not an isolated incident:
after a very short amount of time the salt mill stopped working properly.
I have now had 4. The longest we owned one was 11 months. For the price these should not only last longer but also have a better warranty.
Also even when it was working you had to hold the button down the whole time, and use so much force to hold that button down, that for about a tspn of ground pepper, you'd have a sore thumb for the next 10 minutes. Might as well grind it manually!!
I have a rather inexpensive one I've had for at least five years. I don't even know the brand. But it's very handy to be able to grab and to have ground pepper with one hand quickly. It's easy to adjust the grind for coarseness and the texture of the grind is pretty uniform. It uses four AA batteries and runs a long time on those. The plastic is easy to wipe clean, too. I have two manually operated ones (had one and got a gift) which I like too, but I use the battery-powered one for prep most of the time unless I need to mill a lot of pepper at a time.