We also thought for a long time about getting such a multifunction tap, but then decided against it (for us, the new quooker was under consideration, which also provides cold water and cold sparkling water).
I think the taps are great if you use them a lot and frequently. For example, in the office where several people keep fetching water. Because if you don't get water for a while, the supply line has to run through first until you have cold or sparkling water. Besides, we have a descaling system and to be honest: I prefer to drink raw water (i.e., not descaled). But that means the tap has to be descaled more often, or the filter has to be changed.
We now have a Quooker that only provides us with boiling hot water (descaled, because that is better for tea) and a raw water tap that simply gives us cold water (as cold as it comes from the pipe). The latter goes into bottles and is carbonated with Sodaclub – as much as we want. I like it very sparkling, my husband still, friends medium. I let the Sodaclub carbonate three times, my friend twice.
My Sodaclub is already a good 20 years old (was the first model) and still works perfectly. We're just thinking about buying the one for glass bottles because we find that more pleasant.