I'm running a 730nm flower initiator that turns on 5 minutes before lights out and goes 5 minutes after the lights turn off. Seeing as it was my first run, I don't have any results to compare with, but the Purple OG I was running started showing amber trichs at 7 weeks and the SFV OG (can go 10wk) went milky at Day 1 of Week 9.
I'll be going 13.5/10.5 on this next run with different genetics, so I won't really be able to tell how much it accelerates flowering, hoping to use it's benefits to get a bit better yield.