The “feature” definitely isn’t Nvidia only, they love to frame it that way because $$$, but it’s based off a newer DX12 API, and next year AMD should show up with support for such as well. IE yeah, it’ll be the future. And Archviz is definitely something I can see benefiting early from it. If you think it’s worth the cost (for not a huge perf gain otherwise) then go for it. But as others said, maybe wait till it’s out on UE4?
BTW, it is NOT a replacement for Lightmapping. Which, yeah that sucks but 10 2080ti’s aren’t going to get you the same quality GI as Lightmass, let alone 1. Nor will you be able to not place reflection probes, again, not happening. The hype way overstates things, this isn’t some magic box that can instantly replace predone stuff. But if you say, want a quick preview of different lighting setups, or to never have to deal with planar reflections or something, that it will do.