Performance-wise, there are scalability settings/cvars, but some depend on whether you’re using VSM (virtual shadow maps) and how many lights you’re expecting to have in your scene (especially overlapping/shadow-casting lights). VSMs don’t get quite as soft as ray-traced shadows/Megalights; the latter of which is very experimental, but works with both raytraced shadows and VSMs and can help reduce the cost of overlapping lights. When using VSMs, the recommendation is to gradually increase the radius size until you hit visual diminishing returns; try not to push it much further than that, because it’ll affect performance and visual quality. The SamplesPerRay cvar will effectively limit how soft shadows can get, so this can be adjusted in conjunction with the radius size. The RayCount cvar will make the shadows noisier the lower the number is set. Other than that, it’ll come down to being strategic about light placement, overlap, and the settings mentioned in this thread to best suit your performance needs. Would definitely recommend profiling to get a sense of the tradeoff between certain settings and setups in your scenes.