@Jim_Benson, some years ago I bought a machine from Rio Grande that looks just like that. Needs no fuel or oxygen…sounded promising. It is probably the same machine.
It does work.
The machine itself gets quite hot and can be used only intermittently, or it could burn out. Basically it is just a large (heavy) transformer.
If you look closely at the Gesswein web page the machine says for intermittent use only, just as mine does.
Not only does the machine get hot, but so do the leads. To hold the leads and carbon rods I used leather finger cots, almost of necessity.
It took me some time to work out the dial setting for specific situations, at which point the machine would be really hot. Keep notes so you can dial in the power to suit each task without lengthy trial & error.
Unless using a torch is out of the question for you, I would strongly advise you to get a torch instead. However, if you want to give this a try, I do not use my machine. Make me a modest offer, plus shipping, and you can have mine, plus leather finger tips, plus a bunch of carbon rods, and a bottle of flux for electric soldering. I can’t imagine paying $525 for such a unit.
Actually, this offer is open to anyone who understands that the machine needs to cool down between solderings, and that takes a while. It does work. But…
As an addendum, this would probably be useful for ear posts & such that could be easily melted with a torch. The heating works by conduction only, so there is no blow-by heating that you can get with a misdirected flame.