I have a Fairphone 3+, bought about 6 weeks ago. I might have waited if I'd know this was on the horizon. I flashed mine with /e/ OS (WTF's with that name?) and it has been fantastic. My only complaint is the fingerprint sensor is a little clunky.
Tip: Scotch tape. I was immensely frustrated with the fingerprint sensor on my FP3, which would only register in perfect conditions, so I had to type my password half the time. Somewhere online I read the tip to put a piece of scotch tape over it, which sounded utterly ridiculous, but at the same time so straightforward and harmless that I tried. I have no idea why it works, but I'm only typing my password whenever the "extra security" counter kicks in now.
That's what I'm about to do when my iPhone will pass away eventually (but probably from eSolutions directly). Though I really want my phone to be small, and rather don't want the Predator-like optical aiming device; just a basic up-to-date camera would be fine with me.
Have the FP3+ for about 6 months with /e/OS as well, very happy with it until the USB-C port stopped working. I can either ship the entire phone back for repair (ordered from fairphone.com) or buy the bottom module and replace it myself. I prefer the latter as it's one of the reasons I bought the phone for. Unfortunately that part is currently out of stock... Looking at forums, it seems to be a common issue.
FWIW, the sensor works flawlessly on mine. Maybe how the fingerprint is recorded matters ? I moved my finger slightly between each take in the calibration process.