In my opinion we´re still very far away from a usable realtime path tracing. If you take the largest SLI Rig available you´ll still need several seconds to get a clean result. And those rendertimes I have so far only seen for outdoor scenes, wich are much easier to calculate than an indoor scenario. But to make it usable we would need to get clean results at least 30 times per seconds. Our current hardware is not even close to deliver such speed at the moment. If you take a look at Otoys demo from2014, where they use two Titan cards it still very noisy and that is an outdoor scene. So you´ll only get a clean image when you are standing still for some seconds. the quality while moving is still not acceptable.Brigade 3.0 preview - Real-time path tracing - YouTube demo from 2015 wich is mostly clean uses their cloud service wich are several thousend GPUs. They didn´t state how much actually were used.Brigade Update from OTOY's Presentation at NVIDIA GTC 2015 - YouTube
All those other Realtime GI solutions like VXGI look nice simply but don´t have the quality, specifically the fine GI details, compared to a baked GI. An hybrid GI could be a great solution where the indirect skylight is baked and the sun uses realtime GI. the best realtime GI solution I have seen so far is imperfect shadow mapping. This impressive demo is from 2008 and I really wonder why no one implemented this into an engine.Imperfect Shadow Maps - YouTube I believe if you want those real fine details that you know from non realtime rendering, GI baking will be the standard for many years. So it does make sense to invest time to polish this feature.