I went for this one firstly due to the low price, currently on Amazon at £14.99, but two other factors clinched it for me. The ringers for the last doorbell we had although slim were wide and in fact effectively took up three plug spaces when on a plugboard or multi plug fitting. The old doorbell had a soft touch entirely flush bell push which in fact did not look like a bell push at all with the result that nobody rang it. This one has a well marked bell push which is immediately obvious what it is.
It was easy enough to set it up, just hold down the centre and top buttons on each ringer to set it to learning mode, press the bell push once to link and again to remember the link and that it is. Before that though you have chose which ringer tone you want which is done pressing the top and lower ringer buttons to scroll through what seems to be an endless list of equally annoying ice cream van style tunes. You set the volume using the middle button.
So far it is working well, so fingers crossed.