I have installed many of these
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and only had one failure in 15 years.
However, a word of caution...well quite a few words, actually...
there was a time when these were easy to get, then for a year or two they disappeared from the market, so if you needed a straight replacement, no chance...and all the others on the market needed a bigger cutout in the plinth...
Then, hey presto, they were back!
I needed to install a new one in my own house, got the latest version and......it didn't work on the standard remote, but needed bluetooth and a smartphone etc etc i dunno, but it was all beyond me...fortunately, I had a spare, so installed that instead...long story short, they now seem to sell both versions, and if you have a choice get the old one with the black, 2 button remote which is easy to source.
As for performance, they are very quick to heat up a standard sized kitchen or utility room, don't need a huge cutout, are easy to fit and adjust and do the job well. They just plug in, well the ones with a plug on! A couple came with cable only...I know some will hiss, but honestly, plug into a socket and be done with it.
Oh...and they are not expensive!