In my opinion rethinkdb is super easy to get going and use. The low touch maintenance is what drew me originally.
However, learning to live without transactions takes some rethinking of the approaches taken. It's totally doable but it may not come easy if you're used to transactions in an RDBMS.
Of course in today's distributed multi service multi database world, learning to live without transactions is becoming more and more important anyway.
You can get transactions, but at a cost. Distributed transactions exist, they're just slow (and network-chatty). RethinkDB decided not to go that direction, I guess.
However, learning to live without transactions takes some rethinking of the approaches taken. It's totally doable but it may not come easy if you're used to transactions in an RDBMS.
Of course in today's distributed multi service multi database world, learning to live without transactions is becoming more and more important anyway.