Both exchange are best but I prefer binance exchange is best binance have full security system and also low trading fee so too much people like this we can put or exit any order within seconds on binance FTx is also best but now some feature not good in FTx
i think you have not used ftx exchange yet, both of exchange great btw comparatively low fees in ftx.
i am crazy fan of using binance btw i did not agree to pay high withdrawal fee in eth, so that i feel need to use ftx.