The guys at Apogee instruments just released a video all about the best spectrum for cannabis plant growth and development. Funded by NASA and the USDA. Definitely worth the 23 minute watch - just the right amount of time for a nice session.
A quick summary - all lights work great. Spectrum is irrelevant to yield, so long as plants get the right PPFD. Blue doesn’t change cannabinoid production. Red doesn’t make plants flower better. 20% blue can keep plants short.