There are, fortunately, a huge selection of hair clippers. So I have some tested: a few years ago still wired devices, the last 3 or 4 but only with battery.
The appliances with power cord were robust and easy to handle, downside was of course the cable, the weight and the volume.
The battery units are in contrast usually light and handy and often delicate. In most of these papers, there are those with the "Section height" can be set in several stages. That is often the weak point: the latches of these essays dissemble frequently when using self, or the essays are designed so that they become clogged after a short period with "cut" or both :-(
The Panasonic trimmer is as enjoyable otherwise. It is simple and robust, yet light and fits comfortably in your hand. The essays have given "cutting height" and the hair can be in these essays also not set, but falls down immediately. Since the Harre cutting makes again fun and is done in a few minutes. The price is superior to other devices is relatively high, one has but loose out again when a year, it can save itself hairdresser :-)