[G6Tanuki]

I'd not trust an old-fashioned neon-screwdriver over a modern 'detector pen' such as the Fluke 1AC-II

However one place an old neon-screwdriver _does_ have its uses is in detecting RF parasitic-oscillations in power-amplifiers: you can get a bit of an idea as to whether the oscillations are LF HF or VHF depending on the colour of the glow. [purple means you've probably got a VHF parasitic going on].