Reply to D3s or D500

I am looking for D3s shooters who have also used a D500 for low light action shots.

I’ve always wanted a D3s but as an amateur could never justify the expense. I noticed recently that used prices on MPB have dropped below $675 for bodies in Good condition and shutter counts in the 50 and 60K actuations – a real steal for such an iconic camera. I’ve got a D700 and a selection of FX primes and zooms; also CD cards and EN-EL4a batteries so I am no stranger to FX.

I am looking for your thoughts on how the D3s performs compared to the D500 at ISO 6,400-12,800; I’m planning on shooting indoor volleyball with it when the season reopens after COVID.

I’ve got a D500 and was blown away by its Low Light/High ISO capabilities. Check out this shot made with the D500 at ISO 12,800:

Gamechanger! ISO 12,800 by Tom Kielick

How does the D3s perform? Should I buy one or perhaps a second D500 instead?