Helix is my default, as it's a more mature/stable editor. I fire up Flow Control from time to time to follow how it's developing and for more casual editing. They both do an excellent job overall, but my muscle memory binds me to Helix for now.
(I know Flow Control provides Helix keybindings, but I haven't tried that yet and I generally like to retain the default behavior of an editor so that my user experience is more "portable" across machines.)