I still prefer both MH & HPS.

If it was ONE OR THE OTHER, go with the conversion bulb, not the conversion ballast.

With the conversion bulb, you can always upgrade if these new dual spectrum bulbs prove to be any good.
HARDDON Reviewed by HARDDON on . Is it worth having both MH + HPS? Dont you use MH for vegatative and HPS sodium for Flowering? If you had to choose one, what would be the best? Is the conversion worth it (one Ballast 2 bulbs you switch)? Rating: 5