The idea is very much like knockout and meteor, but the reactivity implementation is completely different. First all it is generic and not designed for just the UI. MobX is completely glitch free and synchronous and has explicit distinction between computed values and reactions (side effects like updating the DOM). More important, MobX determines the right execution other of derivations on the fly, preventing issues with 'double runs' which were a common issue in for example Meteor. These design decision are based on research of common issues with knockout and meteor (like the ones you described) and analyzing what is the root cause of these issues. For that reason you also won't find two way binding in MobX

In practice it turns out to work very well for large apps and many people use it that way (https://twitter.com/_ericelliott/status/766812933804269568)