I never thought about switching after a few weeks b/c I am doing a rotating grow. That is to say I harvest 1 plant ever 3 weeks or so so I have continual harvest rather than all at once, the start over. I was thinking about mixing say a 1kW HPS and a 250W MH, and that is when I stumbled on this sucker.

Maybe I can find room fora third room... 1 for veg under CFLs, 1 for first few weeks of flower under MH, amd a final home stretch flower with HPS! Bah, too much bookwork keeping track lol.