I bought a fairphone 6 recently. It works as you would expect any phone to work with no noticeable downsides.
I paid extra to have /e/OS preinstalled. I could have bought the android version and upgraded it myself, but I wanted to support open source development. I want to try Ubuntu touch, but it hasn't been updated for the fairphone 6 yet.
I can't use any banking apps on /e/OS by default, but that's because the apps require google play services for "security". Enabling these services is possible, but would defeat the purpose of getting the phone to de-google. Bank websites still work, just slightly less convenient.
I dislike the case. It leaves more of the phone exposed than I would like. It does seem to protect the phone from most drops though.
I'm still disappointed by the lack of headphone jack, but I hate Google more.
I was surprised that my favourite feature became the hardware switch. I rebound it to the torch. For moments when you want a light for just a few seconds, it's so much more convenient.