I started off a bit tongue in cheek but taking the thread seriously I have to agree with Mr Vanoord, and not just because I have a big hand in it now.
The Oldham belt weight battery and the feeble little ray of yellow light will soon be a thing of the past.
I have had Oldham lead acid batteries leak, fortunately without damaging ropes etc.
I have also banged my head and had my bulb go; something that an LED does not do.
I can now go underground and see all of the colours in a splendour that was not possible until LED lighting. Small artefacts are seen that I never even noticed before. The biggest slate and limestone mines are lit up like day.
Frankly, there is a large limestone mine that I go in alone, with the Oldham I would not be able to even find my way around.
My avatar is a poor likeness.