Somebody calling himself "Truth teller" (of all things) keeps endlessly, arrogantly, and rudely defending the so-called "suicide shower" units in the comment section on Big Clive's video exploring one -- even in the face of the evidence against him.
Weeeeell... the principle of these showers is tried and true and applied in many European countries. The point is a) that these countries usually have stringent regulations that govern water quality and thereby whether such a heater can safely be installed or not and b) the specific models of tankless electric shower heads sold in South America can be considered poor designs as they do not allow for the appropriately sealed connection of a double-insulated supply cable or flex. In less fancy terms they all seem to have two loose ends of single-insulated wire sticking out and pretty much the only way of connecting them to the supply is using some kind of flying splice secured to the water pipe. If they had a proper terminal box with glands and someone actually made sure they were only installed in places with sufficiently high-resistance water I don't see anything wrong with them. Reality differs though.
Theres a video by someone called GADGET ADDICT hes an English man now living in the philipines he installs and tests one if you Google him you should find it. He has another video called 110 volts without a transformer which shows some decidedly iffy techniques you can use at least in metro manila
Yeah, I've seen Gadget Addict's demonstration too. I'm still not filled with confidence in them, though; even if I don't get electrocuted (in a "proper" installation), it bothers me that they have such a powerful (and compact) element, sitting against plastic, with no thermal cut-outs.
At least fan heaters make an attempt to be fail-safe, even if not all succeed at that...
But the funniest thing, to me, is how TT kept butchering his own maths.