Solid, IMO, SimpleX is still the better choice, but the fact that Keet Chat is serverless 100% is quite appealing.
SimpleX uses relayers, your metadata is sent to relayers and, after is received, the metadata is deleted, keetchat does not use relayers at all is 100% p2p and encrypted e2e. This seems quite appealing but it does add a reliability factor, your messages will stay in your device pinging the receiving party until delivery, this decreases efficiency and could be a negative factor in battery consumption, more test is required.