here are mine experiments by indirect illumination..../bathroom in 50's style/.... all pictures made by IPR rendering.... 6000x4000 pixels....then resized to 1000x667 pixels
rendering time from 12 to 14 hours....by slow graphic card
for me indirect light technique looks really realistic....the only one problem is rendering time for slow comp of-course....but I start to prefer it more than "default" setting