@marcClintDion
IMHO Blender Cylces for UE4 is a bad idea - a very bad idea.
Blender Cycles is unbiased renderer and has NO GLOBAL ILLUMINATION ( only AO ).
GPULightmass (and its predecessor CPULightmass) is better for interior as a biased renderer like VRAY with implemented GI.
That is why Cycles gives so many noise on diffuse channel ( only diffuse channel can be compared ) and needs more samples/time to make all clear ( even with current de-nosie alg.).
I used many renderers for interiors like Thea, Octane, Cycles. And I quite them for UE4 cuz of GI ( and one bake -> many shots/video = time saving that UE4 gives ).
BIASED renderer is best for tasks such as interiors.
GPU Lightmass needs only some small fixer like: fixing shadow splotches and maybe a bit improved GI ( or adjustable ) in the matter of brighter bounced rays ( more energy ) to give much brighter interiors if artist needs that. ( I know it is fake but people like it to see that kind of results and it is more like human brain perception (biased gives) that photography (unbiased gives) ).
That is my humble opinion in that case.