Basically if you want a "product" to use right now and still want to tinker, RM gives you ssh access to a system you can tinker with. RM2 has the best community support for now though.
PineNote works... but yes you will have to be ready to tinker. It's heavy and think but powerful, all the way to having a browser, audio, microSD, etc.
Meanwhile the PocketBook Verse Pro just works, no tinkering, but also tiny and not get for sketches IMHO.
