It's pretty good. Epic added it as part of Unreal Engine to replace their previous hot reload system, which was more similar to the alternatives that people are mentioning here. That previous hot-reload didn't work as well as live coding, was less stable.
Simple dll reloading can work great if you separate state from logic, like shown in handmade hero. If you cannot enforce that then live++ is a good alternative.
Unreal's original Hot Reload system is despised by Unreal developers, and it is a constant source of headaches for new developers using C++ with Unreal, as it can corrupt the (in memory, but also serialized and persistent) UObjects that your game relies on to run.
Live++ ("Live Coding" in Unreal) can still cause these problems if you leave the Reinstancing option on. For anyone doing C++ in Unreal, please please please read this [1] and at the very least make sure to not use the older Hot Reload.
Simple dll reloading can work great if you separate state from logic, like shown in handmade hero. If you cannot enforce that then live++ is a good alternative.
Too bad there's no linux support.