Use the one closest to your location.

You don't have to choose a server where the game server at except the game has been region restricted https://mudfish.net/docs/en/faq/nodes.html#should-i-use-the-basic-mode-and-set-the-better-node-near-game-server-location Network congestion determined by various causalities. It would gets increased on night to early morning in general. Picking a node that shows near flat graph may considered more consistency.