Teardown and look at the new $1395 Siglent SVA1015X 1.5GHz Spectrum and Vector Network Analyser
Well, $2000 when you include the actual VNA option :-/
Seems like they put in a Rubycon cap to make dave happy ^^
Right next to it was a lelon cap.
And the other Caps are different as well.
The gunk on PSU is for transport, though one would usually use that for the Coils and not just caps.
And I'd also not worry too much about the manufacturer but the Series...
As for Lelon low ESR caps, something like RXW or RZW would be nice.
As for the Processor board:
Doesn't that also save some layers on the Mainboard??
Like using 6-8 Layers on the module and 2 or 4 on the main PCB.
That would be my guess why they are doing it.