After last iclone changes i start make some tests . what changes? you can ask..
1 - the great performance bump , iclone is real fast now and is dealing with high poly count as its never do. 
2 - IES light system 

so i start a project animation with 2 not optimized cars for realtime ( each car with 1 milion polys ) 2 avatars , a custom terrain i made in mudbox, and more than 900 speed trees 20 cameras already ( will be more ) . and iclone is dealing with it at 40 fps without VXG and 20 fps with VXGI , for me its amazing speed bump. now in iclone you can import fbx using drag and drop on iclone viewport and 3dxchange get performance bumps updates too.  
so i realized one thing. 3dxchange import a car with 1 milion polys at light speed and convert it for iclone fast too. 
but with a archvizscene wit 1 milion polys but a lot more materials. something like 50 materials + 3dxchange got 30 minutes( the same scene get instant pop up on toolbag 3 and unity  ) . and this dont change when i reduce polycount, i believe its cause the big material quantity. 

so.. why use iclone for archviz??? 
well... after studying all this realtime engines i undestand the power of iclone. and if you compare it against twinmotion for example iclone only lose against reflection probes for realtime reflections. ( you can get a aproach with ibl baking but is not enough )
iclone have a better VXGI system than twinmotion. twinmotion only get global ilumination for sunligh not for artificial lights
iclone can get global ilumination from direct light ( sunlight ) spot lights now with the plus to use IE lights system the emissive props can simulate area lights . iclone have better AO than twinmotion if you use iclone VXGI shadows + HBAO+ in correct way you can pass twinmotion results. more fast rendering for 360 animations. i hope reallusion undestand iclone is more close to fight against twinmotion and lumion very soon on they market.