[ivarru]

Even though Rx/ReactiveX is not easy and simple, it is a big improvement over traditional event-driven programming. The ideas behind Rx are also more general than, say, the actor model. Unfortunately, it is also easy to make a mess with Rx, and when that happens, the debugger is of little help. I often end up writing stuff to the console.

I have not found hot vs cold observables to be a problem in Rx (for C# or Java; I have never used RxJS). In fact, I often use "semi-hot" observables, such as what you get from a BehaviorSubject, which initially gives every new subscriber the latest/current value.

To me, the fact that "the concept of time may be screwed" when using Rx, is a good thing because of the flexibility it gives. In particular, it can be very useful for testing; but I do struggle with Rx scheduling at times. At some point there will hopefully be more information available on how to use Rx effectively in complex, real-life scenarios. Maybe someone should write a book on Rx design patterns?