Eventhough I spend nearly my entire life thinking about and growing plants for bonsai, I find it too inconvenient to have to hand water my own bonsai. I switched to an automatic system years ago. In some ways it is more advantageous than hand watering. The disadvantage is that you don't get to see your bonsai everyday to spot problems, unless you have some other routine for visiting every plant every day.
For my larger bonsai that are lined up singularly on a narrow bench, I just put these mist heads in strategic positions so that the top of the soil gets a pretty much direct spray. I don't worry about the foliage. It does get wet from the fog like mist, but the water is mostly directed at the rootball.
You can operate such a system just by connecting to a hose bib and turning it on and off manually. But the beauty of such a system is that it can be easily automated with a hard wired irrigation timer and electric 24V solenoid valve. Battery operated timers are just too erratic for this purpose. With this system you can pretty much leave for a week or two and your plants will be fine if you have someone check everyday to see if the system came on, and if this person has the wherewithal to fix it if it breaks. In general, a hard wired system is pretty fool proof if you have a nice fresh backup battery.
Although these mist heads have larger diameter orifices than traditional drip emitters, a filter is still a must. Fine mesh filters tend to clog too often for me and really are not necessary since most fine particles will pass right through the emitter anyway. I find that about 60 mesh is right. This should be a fairly large filter so you don't have to check it too often and to give you a larger reserve. Netafim filters with 3/4 or 1 inch outlets are about the right size and have a choice of filter meshes.