I have used a rotary shaver for several years and decided to return to a vibrating foil-type shaver - F4. My expectations were apparently too high. I can't get a really close shave unless I spend an inordinate amount of time going over and over. Also, if I skip a day it is very difficult for the foil head to "capture" the longer hairs.
Finally when the head pivots, the motor slows down noticeably. This can't be good for the long-term durability.
I have only had it for a couple weeks. I hate to give up on it, but I don't like to start out each day feeling stressed about shaving.