My perspective is that they are two tools that provide a similar set of functionality (admittedly, shadow provides more help in the interop department with NPM). Personally, I like Shadow and admire the work thheller is doing, but I have no reason to switch my projects to Shadow at this point in time. Hope this helps answer the question 🙂
I view figwheel as a development-ony tool to enable hot code reloading. Shadow does that too. It is also a build tool for production. I prefer vanilla cljs.main building for production.