I've had it for over two years - approaching three. Used weekly, not only for my heat-treating/hardening, but I also do a ramped spherodizing annealing process on a lot of my stuff which is about a 10-12 hour programmed ramp cycle.
No issues in three years other than one of the two elements burned out about a month ago. Ordered two to have a spare. 30 bucks. Easy replacement.
The lady told me that in ceramic places where these things run all day, every day, elements can be replaced every six months or so. But in knife use, quite honestly, most of the time it just sits there.
But when you need it - it's invaluable.
It gets my vote of confidence.