An almost fair comparison.
Some things to note:
1. The Nixies on the Jane are slightly more liberally lubed compared to the others. They were done and sent by Alexotos in a giveaway board I won The rest is more or less the same.

1. Glare has DCS and not GMK. In my experience with both on it, there is not a huge difference.

2. Merisi has the CEM3 pcb, the others have FR4.

Also, stabs may be different - they are all lubed and tuned.

Switches in the first three builds are the hand modded Nixies from ‪Unikeys.
Watch more comparisons and typing tests on my channel: https://www.youtube.com/@rishavrastogi

Keyboards:

1. Merisi 500c/m with GMK Prussian Alert
   
2. Geon Glare TKl with Brass Bottom with DCS Flex Kits
   
3. NRD Kaze TKL with GMK Klassiker
   
4. Jane V3 Rubrehose with GMK Mudbeam

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