I’ve used both and they’re both great. I didn’t like the migration process for Bitwarden -> 1Password. I think I ended up downloading some python script to change the format of my Bitwarden export to a format 1Password could understand. I imagine the migration process is a lot better now since it’s been about a year since I’ve done that.
Outside of that, I like the design of 1Password better, and it also tends to auto fill more reliably as well. iirc Bitwarden has auto fill as well, but it didn’t work great for me, so I ended up copy pasting passwords instead. Not a huge deal, just something to keep in mind.