"I wasn't aware that this sort of thing was available, but pleasantly surprised to find it would fit a radiator I had just bought. Had the radiator working before it was plumbed in. Useful to use in the summer, disconnected during the winter. My electrical set-up allows me to use a simple time-switch, instead of the rather expensive thermostatic switches available. No time yet to assess reliability. No leaks so far."
"I installed this with no leaks on my new pipe-work. When I can to pressurise the system the element leaked from the inadequate "o" ring at its connection. Even after tightening it still leaked. Luckily I had some spare "o" rings to add to the existing one to seal it with no leaks. The product needs some testing and improvement. Only the "o" rings let it down. I lost a dose of inhibitor as it was drained out."