I installed these 500A 500K and 500B 500K pushpull pots on my Samiac AV6 to get coil splitting and series/parallel and Phase toggle(Jimmy Page Wiring).
tapering is good on these pots. main 3legs of pot are big enough for soldering but vertical 6 legs are very small tightly spaced and delicate. push/pull action works well but it feels very delicate to handle. overall built quality is below average but it does serve the purpose.
i might replace them in future with CTS or Bourns.
recommend these only if you are experimenting or just want to use them for demo mod projects