[Nonfractal]

Good post.

 ..but they all seem to suffer apart from Thunderslot who use sensible size grub screws. I don't have any NSRs.

Gordon, 
The designer behind ThunderSlot is the same as the earlier NSRs,
If you see "NSR by GM" on an NSR chassis it will have been designed by Giovanni Montiglio.


Thunderslot will have a presence the UKSlot Fest 
I'll ask Giovanni about set screw sizes. 
Why bigger? That's obvious 
Why Imperial UNC4-40 , that's a mystery.