There are various types of these hot water dispensers. For last two years I have had a cheapo one, Did the job, but had no filter, and no way of changing heat settings, and had to watch it to ensure did not have cups spilling over. Even so, it was so very useful, hot water always immediate, used it for percolated coffee, making gravy, easy to use with t.pot and saucepan. Kept a small jug and filled it from cold water tap regularly.
I have recently had to replace it, as it started dripping, bought a much more up market one, filter, four different heat settings, so I can do my black tea, green tea, instant coffee etc. at heat recommended for them. It dispenses three different volumes, so no more having to worry about me flooding the worktop. Love it - I find using a kettle difficult and potentially dangerous for me. This is absolutely safe, and very instant. This time I have gone for a 4 litre container, so only need to fill it (with jug) usually once a day.
Does look a little more like the the Flight Board of The Enterprise to use, but once used to it, find it surprisingly easy and quick.