Google dialer?
Ad free, not slow, but collecting all possible data on your calls.
I like that it's blocking the spam calls, I get 10 spam calls for each real call. Unfortunately that needs to send back to them all my phone calls with their caller id.
I hate how it shows the call log. It only shows the latest action ever for a number and doesn't even show the time. This is especially infuriating when you need to see what time someone called. For example my doctor office called to move my appointment, then when I showed up they said that wasn't true and wanted to charged me for a no-show. I wasn't able to prove immediately that they called me on which day and at which time to move the appointment because the "simplified" call log only shows the latest call action which was that I called back several days after that.